Compstatin Analogs for Treatment of Neuropathic Pain

ABSTRACT

In some aspects, the present invention provides methods of treating a subject in need of treatment for neuropathic pain, the method comprising administering a compstatin analog to the subject. In some embodiments, the compstatin analog is administered parenterally, e.g., intravenously.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and priority to U.S. ProvisionalPatent Application No. 61/357,448, filed Jun. 22, 2010, the entirecontents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

Pain is a major symptom in many medical conditions and a common reasonthat prompts individuals to seek medical attention. Neuropathic pain isa type of pain that may arise as a consequence of a lesion or diseaseaffecting the somatosensory system. Neuropathic pain is typicallycharacterized by patients as burning, aching, or shooting. The pain maybe provoked by normally innocuous stimuli (allodynia). It is alsocommonly associated with hyperalgesia (increased pain intensity evokedby normally painful stimuli) and abnormal sensations, such aspins-and-needles or electric-shock-like sensations. Neuropathic pain canbe very severe and disabling and can result in significant functional,psychological, and/or social consequences.

Neuropathic pain has been estimated to affect up to 6%-8% of the generalpopulation. It can arise from a variety of causes that involve thebrain, spinal cord, and/or peripheral nerves, including cervical orlumbar radiculopathy, diabetic neuropathy, postherpetic neuralgia,HIV-related neuropathy, and spinal cord injury, among others.Neuropathic pain can arise following physical injury, persisting despiteresolution of the inciting damage to the nerve and the surroundingtissues.

Regardless of the underlying cause of neuropathic pain, common treatmentgoals are to decrease pain and/or improve function. Tricyclicantidepressants, anticonvulsants, and opioid analgesics are frequentlyprescribed. However, these medications frequently fail to provideadequate pain relief and/or are associated with troubling side effects.People with neuropathic pain have been found to generate 3-fold higherhealth care costs compared with matched controls. In the United States,health care, disability and related costs associated with neuropathicpain have been estimated at almost $40 billion annually.

There is a considerable need for more effective pharmacologicaltherapies for neuropathic pain.

SUMMARY OF THE INVENTION

The invention provides a method of treating a subject suffering fromneuropathic pain, the method comprising administering a compstatinanalog to the subject. In some embodiments the compstatin analog isadministered parenterally, e.g., intravenously. In some embodiments, thesubject suffers from painful diabetic neuropathy, post-herpeticneuralgia, trigeminal neuralgia, cancer related neuropathic pain,chemotherapy-associated neuropathic pain, HIV related neuropathic pain(e.g., from HIV neuropathy), central/post-stroke neuropathic pain,neuropathy associated with back pain, e.g., low back pain (e.g, fromradiculopathy such as spinal root compression, e.g., lumbar rootcompression), peripheral nerve injury pain, phantom limb pain,polyneuropathy, spinal cord injury related pain, myelopathy, and/ormultiple sclerosis. All articles, books, patent applications, patents,other publications, and electronic databases mentioned in thisapplication are incorporated herein by reference. In the event of aconflict between the specification and any of the incorporatedreferences the specification (including any amendments thereto) shallcontrol. Unless otherwise indicated, art-accepted meanings of terms andabbreviations are used herein.

DEFINITIONS

The terms “approximately” or “about” in reference to a number generallyinclude numbers that fall within ±10%, in some embodiments ±5%, in someembodiments ±1%, in some embodiments ±0.5% of the number unlessotherwise stated or otherwise evident from the context (except wheresuch number would impermissibly exceed 100% of a possible value).

A “complement component” or “complement protein” is a protein that isinvolved in activation of the complement system or participates in oneor more complement-mediated activities. Components of the classicalcomplement pathway include, e.g., C1q, C1r, C1s, C2, C3, C4, C5, C6, C7,C8, C9, and the C5b-9 complex, also referred to as the membrane attackcomplex (MAC) and active fragments or enzymatic cleavage products of anyof the foregoing (e.g., C3a, C3b, C4a, C4b, C5a, etc.). Components ofthe alternative pathway include, e.g., factors B, D, and properdin.Components of the lectin pathway include, e.g., MBL2, MASP-1, andMASP-2. Complement components also include cell-bound receptors forsoluble complement components, wherein such receptor mediates one ormore biological activities of such soluble complement componentfollowing binding of the soluble complement component. Such receptorsinclude, e.g., C5a receptor (C5aR), C3a receptor (C3aR), ComplementReceptor 1 (CR1), Complement Receptor 2 (CR2), Complement Receptor 3(CR3, also known as CD45), etc. It will be appreciated that the term“complement component” is not intended to include those molecules andmolecular structures that serve as “triggers” for complement activation,e.g., antigen-antibody complexes, foreign structures found on microbialor articifial surfaces, etc.

A “complement regulatory protein” is a protein involved in regulatingcomplement activity. A complement regulatory protein may down-regulatecomplement activity by, e.g., inhibiting complement activation or byinactivating or accelerating decay of one or more activated complementproteins. Examples of complement regulatory proteins include C1inhibitor, C4 binding protein, clusterin, vitronectin, CFH, factor I,and the cell-bound proteins CD46, CD55, CD59, CR1, CR2, and CR3.

“Linked”, as used herein with respect to two or more moieties, meansthat the moieities are physically associated or connected with oneanother to form a molecular structure that is sufficiently stable sothat the moieties remain associated under the conditions in which thelinkage is formed and, preferably, under the conditions in which the newmolecular structure is used, e.g., physiological conditions. In certainpreferred embodiments of the invention the linkage is a covalentlinkage. In other embodiments the linkage is noncovalent. Moieties maybe linked either directly or indirectly. When two moieties are directlylinked, they are either covalently bonded to one another or are insufficiently close proximity such that intermolecular forces between thetwo moieties maintain their association. When two moieties areindirectly linked, they are each linked either covalently ornoncovalently to a third moiety, which maintains the association betweenthe two moieties. In general, when two moieties are referred to as beinglinked by a “linking moiety” or “linking portion”, the linkage betweenthe two linked moieties is indirect, and typically each of the linkedmoieties is covalently bonded to the linking moiety. Two moieties may belinked using a “linker”. A linker can be any suitable moiety that reactswith the entities to be linked within a reasonable period of time, underconditions consistent with stability of the entities (portions of whichmay be protected as appropriate, depending upon the conditions), and insufficient amount, to produce a reasonable yield. Typically the linkerwill contain at least two functional groups, one of which reacts with afirst entity and the other of which reacts with a second entity. It willbe appreciated that after the linker has reacted with the entities to belinked, the term “linker” may refer to the part of the resultingstructure that originated from the linker, or at least the portion thatdoes not include the reacted functional groups. A linking moiety maycomprise a portion that does not participate in a bond with the entitiesbeing linked, and whose main purpose may be to spatially separate theentities from each other. Such portion may be referred to as a “spacer”.

“Polypeptide”, as used herein, refers to a polymer of amino acids,optionally including one or more amino acid analogs. A protein is amolecule composed of one or more polypeptides. A peptide is a relativelyshort polypeptide, typically between about 2 and 60 amino acids inlength, e.g., between 8 and 40 amino acids in length. The terms“protein”, “polypeptide”, and “peptide” may be used interchangeably.Polypeptides used herein may contain amino acids such as those that arenaturally found in proteins, amino acids that are not naturally found inproteins, and/or amino acid analogs that are not amino acids. As usedherein, an “analog” of an amino acid may be a different amino acid thatstructurally resembles the amino acid or a compound other than an aminoacid that structurally resembles the amino acid. A large number ofart-recognized analogs of the 20 amino acids commonly found in proteins(the “standard” amino acids) are known. One or more of the amino acidsin a polypeptide may be modified, for example, by the addition of achemical entity such as a carbohydrate group, a phosphate group, afarnesyl group, an isofarnesyl group, a fatty acid group, a linker forconjugation, functionalization, or other modification, etc. Certainnon-limiting suitable analogs and modifications are described inWO2004026328. The polypeptide may be acetylated, e.g., at the N-terminusand/or amidated, e.g., at the C-terminus.

“Reactive functional groups” as used herein refers to groups including,but not limited to, olefins, acetylenes, alcohols, phenols, ethers,oxides, halides, aldehydes, ketones, carboxylic acids, esters, amides,cyanates, isocyanates, thiocyanates, isothiocyanates, amines,hydrazines, hydrazones, hydrazides, diazo, diazonium, nitro, nitriles,mercaptans, sulfides, disulfides, sulfoxides, sulfones, sulfonic acids,sulfinic acids, acetals, ketals, anhydrides, sulfates, sulfenic acidsisonitriles, amidines, imides, imidates, nitrones, hydroxylamines,oximes, hydroxamic acids thiohydroxamic acids, allenes, ortho esters,sulfites, enamines, ynamines, ureas, pseudoureas, semicarbazides,carbodiimides, carbamates, imines, azides, azo compounds, azoxycompounds, and nitroso compounds. Reactive functional groups alsoinclude those frequently used to prepare bioconjugates, e.g.,N-hydroxysuccinimide esters, maleimides, sulfhydryls, and the like (see,for example, Hermanson, G., Bioconjugate Techniques, Academic press, SanDiego, 1996 or the second edition thereof, published in 2008, Elsevier).Methods to prepare each of these functional groups are well known in theart and their application to or modification for a particular purpose iswithin the ability of one of skill in the art (see, for example, Sandlerand Karo, eds. ORGANIC FUNCTIONAL GROUP PREPARATIONS, Academic Press,San Diego, 1989).

A “subject” treated according to the instant invention is typically ahuman, a non-human primate, or a lower animal (e.g., a mouse or rat),which expresses or contains at least some primate (e.g., human)complement component C3 and, optionally, one or more additional primatecomplement component(s). In some embodiments the subject is male. Insome embodiments the subject is female. In some embodiments the subjectis an adult, e.g., a human at least 18 years of age, e.g., between 18and 100 years of age.

As used herein, “alkyl” refers to a saturated straight, branched, orcyclic hydrocarbon having from about 1 to about 22 carbon atoms (and allcombinations and subcombinations of ranges and specific numbers ofcarbon atoms therein), with from about 1 to about 12, or about 1 toabout 7 carbon atoms being preferred in certain embodiments of theinvention. Alkyl groups include, but are not limited to, methyl, ethyl,n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, n-pentyl, cyclopentyl,isopentyl, neopentyl, n-hexyl, isohexyl, cyclohexyl, cyclooctyl,adamantyl, 3-methylpentyl, 2,2-dimethylbutyl, and 2,3-dimethylbutyl.

As used herein, “halo” refers to F, Cl, Br or I.

As used herein, “alkanoyl” refers to an optionally substituted straightor branched aliphatic acyclic residue having about 1 to 10 carbon atoms(and all combinations and subcombinations of ranges and specific numberof carbon atoms) therein, e.g., from about 1 to 7 carbon atoms. Alkanoylgroups include, but are not limited to, formyl, acetyl, propionyl,butyryl, isobutyryl, pentanoyl, isopentanoyl, 2-methyl-butyryl,2,2-dimethoxypropionyl, hexanoyl, heptanoyl, octanoyl, and the like.“Lower alkanoyl” refers to an optionally substituted straight orbranched aliphatic acyclic residue having about 1 to about 5 carbonatoms (and all combinations and subcombinations of ranges and specificnumber of carbon atoms). Such groups include, but are not limited to,formyl, acetyl, propionyl, butyryl, isobutyryl, pentanoyl, isopentanoyl,etc.

As used herein, “aryl” refers to an optionally substituted, mono- orbicyclic aromatic ring system having from about 5 to about 14 carbonatoms (and all combinations and subcombinations of ranges and specificnumbers of carbon atoms therein), with from about 6 to about 10 carbonsbeing preferred. Non-limiting examples include, for example, phenyl andnaphthyl.

As used herein, “aralkyl” refers to alkyl radicals bearing an arylsubstituent and have from about 6 to about 22 carbon atoms (and allcombinations and subcombinations of ranges and specific numbers ofcarbon atoms therein), with from about 6 to about 12 carbon atoms beingpreferred in certain embodiments. Aralkyl groups can be optionallysubstituted. Non-limiting examples include, for example, benzyl,naphthylmethyl, diphenylmethyl, triphenylmethyl, phenylethyl, anddiphenylethyl.

As used herein, the terms “alkoxy” and “alkoxyl” refer to an optionallysubstituted alkyl-O— group wherein alkyl is as previously defined.Exemplary alkoxy and alkoxyl groups include methoxy, ethoxy, n-propoxy,i-propoxy, n-butoxy, and heptoxy.

As used herein, “carboxy” refers to a —C(═O)OH group.

As used herein, “alkoxycarbonyl” refers to a —C(═O)O-alkyl group, wherealkyl is as previously defined.

As used herein, “aroyl” refers to a —C(═O)-aryl group, wherein aryl isas previously defined. Exemplary aroyl groups include benzoyl andnaphthoyl.

Typically, substituted chemical moieties include one or moresubstituents that replace hydrogen. Exemplary substituents include, forexample, halo, alkyl, cycloalkyl, aralkyl, aryl, sulfhydryl, hydroxyl(—OH), alkoxyl, cyano (—CN), carboxyl (—COOH), —C(═O)O-alkyl,aminocarbonyl (—C(═O)NH₂), —N-substituted aminocarbonyl (—C(═O)NHR″),CF₃, CF₂CF₃, and the like. In relation to the aforementionedsubstituents, each moiety R″ can be, independently, any of H, alkyl,cycloalkyl, aryl, or aralkyl, for example.

As used herein, “L-amino acid” refers to any of the naturally occurringlevorotatory alpha-amino acids normally present in proteins or the alkylesters of those alpha-amino acids. The term D-amino acid” refers todextrorotatory alpha-amino acids. Unless specified otherwise, all aminoacids referred to herein are L-amino acids.

As used herein, an “aromatic amino acid” is an amino acid that comprisesat least one aromatic ring, e.g., it comprises an aryl group.

As used herein, an “aromatic amino acid analog” is an amino acid analogthat comprises at least one aromatic ring, e.g., it comprises an arylgroup.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS OF THE INVENTION

The present invention provides compositions and methods for treating asubject suffering from neuropathic pain. In one aspect the inventionprovides a method of treating a subject suffering from neuropathic pain,the method comprising administering a compstatin analog to the subject.As described in further detail below, compstatin analogs are complementinhibitors that bind to complement component C3 and inhibit itscleavage, thus inhibiting complement activation via the three majorcomplement activation pathways. Compstatin analogs are highly effectivein reducing formation of complement system effectors. The inventionencompasses the recognition of the benefit of compstatin analogs fortreatment of neuropathic pain.

Neuropathic pain has been defined as pain initiated or caused by aprimary lesion or dysfunction in the nervous system, in particular, painarising as a direct consequence of a lesion or disease affecting thesomatosensory system. For example, neuropathic pain may arise fromlesions that involve the somatosensory pathways with damage to smallfibres in peripheral nerves and/or to the spino-thalamocortical systemin the CNS. Neuropathic pain is considered to arise at least in partfrom mechanisms other than as a direct result of stimulation ofperipheral sensory endings by actually or potentially tissue-damagingstimuli. Neuropathic pain can occur because of dysfunction or disease ofthe nervous system at the peripheral and/or central level. Neuropathicpain may be classified by etiology and/or by the presumed ordemonstrated site of neurologic involvement (central or peripheral).However, both peripheral and central nervous system lesions maycontribute to many types of neuropathic pain. Neuropathic pain can bechronic, e.g., lasting for at least 3, 6, 9, 12, 24, 36 months, or more,e.g., as measured from the onset of the pain. It can be spontaneous(stimulus-independent or spontaneous pain) or elicited by a stimulus(stimulus-dependent or stimulus-evoked pain). Spontaneous neuropathicpain is often described as a constant burning sensation, but it may alsoinclude intermittent shooting, lancinating sensations, electricshock-like pain, and/or dysesthesias (i.e. abnormal and unpleasantsensations). .It will be appreciated that neuropathic pain can becontinuous or intermittent and may wax and wane during a time interval.It can be associated with allodynia, hyperalgesia, and/or paresthesias.In some embodiments of the invention, a compstatin analog isadministered to treat a subject with neuropathic pain associated with anidentified neurologic lesion. A neurologic lesion can be identifiedbased on neurological examination, laboratory tests, and/or imagingstudies, etc., and can take into account the existence of a disease(e.g., diabetes, HIV), known to be associated with nerve damage.

Neuropathic pain can arise from autoimmune disease (e.g., multiplesclerosis), metabolic diseases (e.g., diabetes), infection (e.g., viraldiseases such as shingles), vascular disease (e.g., stroke), trauma(e.g., injury, surgery), and cancer. For example, neuropathic pain canbe pain that persists after healing of an injury or after cessation of astimulus of peripheral nerve endings or pain that arises due to damageto nerves. Exemplary conditions of or associated with neuropathic paininclude painful diabetic neuropathy, post-herpetic neuralgia (e.g., painpersisting or recurring at the site of acute herpes zoster 3 or moremonths after the acute episode), trigeminal neuralgia, cancer relatedneuropathic pain, chemotherapy-associated neuropathic pain, HIV-relatedneuropathic pain (e.g., from HIV neuropathy), central/post-strokeneuropathic pain, neuropathy associated with back pain, e.g., low backpain (e.g., from radiculopathy such as spinal root compression, e.g.,lumbar root compression, which compression may arise due to discherniation), spinal stenosis, peripheral nerve injury pain, phantom limbpain, polyneuropathy, spinal cord injury related pain, myelopathy, andmultiple sclerosis. In certain embodiments of the invention a compstatinanalog is administered to treat neuropathic pain in a subject with oneor more of the afore-mentioned conditions.

Neuropathic pain can be diagnosed using methods known in the art suchas, but not limited to, medical/surgical history and/or neurologicexamination. A neurological examination that includes an accuratesensory examination is often sufficient to reach a diagnosis in theclinical setting. Nerve conduction studies and somatosensory-evokedpotentials may be used to demonstrate and/or localize a peripheral orcentral nervous lesion. it will be appreciated that the diagnosis ofneuropathic pain is within the discretion of the skilled practitioner. Avariety of clinical tools are available that can be used to assess paincharacteristics and, if desired, to determine whether a subject haschronic pain of predominantly neuropathic origin. Such tools can bebased on questions (eliciting descriptions of the pain) and/or physicaltests. For example, the Leeds Assessment of Neuropathic Symptoms andSigns pain scale (LANSS) was developed as a clinic based instrument foridentifying patients whose pain is dominated by neuropathic mechanisms(Bennett M: The LANSS Pain Scale: the Leeds assessment of neuropathicsymptoms and signs. Pain 92:147-157, 2001). It has been validated and isalso available as a a self-complete version, the S-LANSS, which wasfound to be valid and reliable at identifying chronic pain ofpredominantly neuropathic origin (POPNO) on the basis of the patient'scurrent symptoms and signs in comparison with expert clinical judgement(Bennett MI, et al. The S-LANSS score for identifying pain ofpredominantly neuropathic origin: validation for use in clinic andpostal research. J Pain. 6:149-158, 2005; see also Torrance, N, et al.,The Journal of Pain, 7(4): 281-289, 2006). The DN4 is another assessmenttool that allows identification of chronic pain with neuropathiccharacteristics with a very good specificity and sensitivity (BouhassiraD, et al. Comparison of pain syndromes associated with nervous orsomatic lesions and development of a new neuropathic pain diagnosticquestionnaire (DN4). Pain. 114:29-36, 2005; see also Bouhassira D, etal. Pain 136, 380-387, 2008). It consists of seven interview questionsand three physical tests. Administration of the DN4 interview alone canbe used to identify subjects with POPNO. Another assessment tool thatcould be used to distinguish between neuropathic and non-neuropathicpain, in particular low back pain, and/or to classify subjects is theStandardized Evaluation of Pain (StEP) (Scholz, J. et al., PLoS Med. Anovel tool for the assessment of pain: validation in low back pain,2009). In some embodiments, a compstatin analog is administered to treata subject suffering from chronic pain that has characteristics ofneuropathic pain (e.g., based on pain descriptors) and/or physicaltest(s). In some embodiments, the subject has pain that meets thecriteria for POPNO based on an assessment tool such as the LANNS,S-LANNS, or DN4. In some embodiments, the subject has POPNO and lacks anidentified nervous system lesion. In some embodiments, the subject hasPOPNO and the pain is associated with an identified nervous systemlesion. In some embodiments, a compstatin analog is used to treat asubject with moderate or severe pain, based on a pain intensity score(discussed further below). In some embodiments, the intensity is atleast 6 on a 0-10 point scale (discussed further below). In someembodiments, a compstatin analog is used to treat a subject in need oftreatment for neuropathic pain, e.g., a subject suffering fromneuropathic pain or a condition associated with neuropathic pain,wherein the subject has not been diagnosed with and/or does not alsosuffer from a different disorder or condition for which compstatinanalog treatment would be appropriate and/or wherein the subject is notbeing treated with a compstatin analog for such a disorder or condition.In some embodiments, a compstatin analog is used to treat a subject inneed of treatment for neuropathic pain, e.g., a subject suffering fromneuropathic pain or a condition associated with neuropathic pain,wherein the subject has been diagnosed with and/or also suffers from adifferent disorder or condition for which compstatin analog treatmentwould be appropriate but wherein the subject is not being treated with acompstatin analog for such a disorder or condition or, in someembodiments, if the subject is being treated with a compstatin analogfor such a disorder or condition, a different dose, formulation,compstatin analog, and/or route or method of administration, etc., isused.

Complement System

In order to facilitate an understanding of the invention, and withoutintending to limit the invention in any way, this section provides anoverview of complement and its pathways of activation. Further detailsare found, e.g., in Kuby Immunology, 6^(th) ed., 2006; Paul, W. E.,Fundamental Immunology, Lippincott Williams & Wilkins; 6^(th) ed., 2008;and Walport M J., Complement. First of two parts. N Engl J Med.,344(14):1058-66, 2001.

Complement is an arm of the innate immune system that plays an importantrole in defending the body against infectious agents. The complementsystem comprises more than 30 serum and cellular proteins that areinvolved in three major pathways, known as the classical, alternative,and lectin pathways. The classical pathway is usually triggered bybinding of a complex of antigen and IgM or IgG antibody to C1 (thoughcertain other activators can also initiate the pathway). Activated C1cleaves C4 and C2 to produce C4a and C4b, in addition to C2a and C2b.C4b and C2a combine to form C3 convertase, which cleaves C3 to form C3aand C3b. Binding of C3b to C3 convertase produces C5 convertase, whichcleaves C5 into C5a and C5b. C3a, C4a, and C5a are anaphylotoxins andmediate multiple reactions in the acute inflammatory response. C3a andC5a are also chemotactic factors that attract immune system cells suchas neutrophils.

The alternative pathway is initiated by, e.g., microbial surfaces andvarious complex polysaccharides. In this pathway, C3b, resulting fromcleavage of C3, which occurs spontaneously at a low level, binds totargets, e.g., on cell surfaces and forms a complex with factor B, whichis later cleaved by factor D, resulting in a C3 convertase. C1eavage ofC3 and binding of another molecule of C3b to the C3 convertase givesrise to a C5 convertase. C3 and C5 convertases of this pathway areregulated by CR1, DAF, MCP, and fH. The mode of action of these proteinsinvolves either decay accelerating activity (i.e., ability to dissociateconvertases), ability to serve as cofactors in the degradation of C3b orC4b by factor I, or both.

The C5 convertases produced in both pathways cleave C5 to produce C5aand C5b. C5b then binds to C6, C7, and C8 to form C5b-8, which catalyzespolymerization of C9 to form the C5b-9 membrane attack complex (MAC).The MAC inserts itself into target cell membranes and causes cell lysis.Small amounts of MAC on the membrane of cells may have a variety ofconsequences other than cell death.

The lectin complement pathway is initiated by binding of mannose-bindinglectin (MBL) and MBL-associated serine protease (MASP) to carbohydrates.The MB1-1 gene (known as LMAN-1 in humans) encodes a type I integralmembrane protein localized in the intermediate region between theendoplasmic reticulum and the Golgi. The MBL-2 gene encodes the solublemannose-binding protein found in serum. In the human lectin pathway,MASP-1 and MASP-2 are involved in the proteolysis of C4 and C2, leadingto a C3 convertase described above.

Complement activity is regulated by various mammalian proteins referredto as complement control proteins (CCPs) or regulators of complementactivation (RCA) proteins (U.S. Pat. No. 6,897,290). These proteinsdiffer with respect to ligand specificity and mechanism(s) of complementinhibition. They may accelerate the normal decay of convertases and/orfunction as cofactors for factor I, to enzymatically cleave C3b and/orC4b into smaller fragments. CCPs are characterized by the presence ofmultiple (typically 4-56) homologous motifs known as short consensusrepeats (SCR), complement control protein (CCP) modules, or SUSHIdomains, about 50-70 amino acids in length that contain a conservedmotif including four disulfide-bonded cysteines (two disulfide bonds),proline, tryptophan, and many hydrophobic residues. The CCP familyincludes complement receptor type 1 (CR1; C3b:C4b receptor), complementreceptor type 2 (CR2), membrane cofactor protein (MCP; CD46),decay-accelerating factor (DAF), complement factor H (fH), andC4b-binding protein (C4bp). CD59 is a membrane-bound complementregulatory protein unrelated structurally to the CCPs.

Compstatin Analogs

Compstatin is a cyclic peptide that binds to C3 and inhibits complementactivation by, e.g., inhibiting cleavage of C3 to C3a and C3b byconvertase. U.S. Pat. No. 6,319,897 describes a peptide having thesequence Ile-[Cys-Val-Val-Gln-Asp-Trp-Gly-His-His-Arg-Cys]-Thr (SEQ IDNO: 1), with the disulfide bond between the two cysteines denoted bybrackets. It will be understood that the name “compstatin” was not usedin U.S. Pat. No. 6,319,897 but was subsequently adopted in thescientific and patent literature (see, e.g., Morikis, et al., ProteinSci., 7(3):619-27, 1998) to refer to a peptide having the same sequenceas SEQ ID NO: 2 disclosed in U.S. Pat. No. 6,319,897, but amidated atthe C terminus as shown in Table 1 (SEQ ID NO: 8). The term “compstatin”is used herein consistently with such usage (i.e., to refer to SEQ IDNO: 8). Compstatin analogs that have higher complement inhibitingactivity than compstatin have been developed. See, e.g., WO2004/026328(PCT/US2003/029653), Morikis, D., et al., Biochem Soc Trans. 32(Pt1):28-32, 2004, Mallik, B., et al., J. Med. Chem., 274-286, 2005;Katragadda, M., et al. J. Med. Chem., 49: 4616-4622, 2006; WO2007062249(PCT/US2006/045539); WO2007044668 (PCT/US2006/039397), WO/2009/046198(PCT/US2008/078593); WO/2010/127336 (PCT/US2010/033345) and discussionbelow.

Compstatin analogs may be acetylated or amidated, e.g., at theN-terminus and/or C-terminus. For example, compstatin analogs may beacetylated at the N-terminus and amidated at the C-terminus. Consistentwith usage in the art, “compstatin” as used herein, and the activitiesof compstatin analogs described herein relative to that of compstatin,refer to compstatin amidated at the C-terminus (Mallik, 2005, supra).

Concatamers or multimers of compstatin or a complement inhibiting analogthereof are also of use in the present invention.

As used herein, the term “compstatin analog” includes compstatin and anycomplement inhibiting analog thereof. The term “compstatin analog”encompasses compstatin and other compounds designed or identified basedon compstatin and whose complement inhibiting activity is at least 50%as great as that of compstatin as measured, e.g., using any complementactivation assay accepted in the art or substantially similar orequivalent assays. Certain suitable assays are described in U.S. Pat.No. 6,319,897, WO2004/026328, Morikis, supra, Mallik, supra, Katragadda2006, supra,WO2007062249 (PCT/US2006/045539); WO2007044668(PCT/US2006/039397), WO/2009/046198 (PCT/US2008/078593); and/orWO/2010/127336 (PCT/US2010/033345). The assay may, for example, measurealternative or classical pathway-mediated erythrocyte lysis or be anELISA assay. In some embodiments, an assay described in WO/2010/135717(PCT/US2010/035871) is used.

The activity of a compstatin analog may be expressed in terms of itsIC₅₀ (the concentration of the compound that inhibits complementactivation by 50%), with a lower IC₅₀ indicating a higher activity asrecognized in the art. The activity of a preferred compstatin analog foruse in the present invention is at least as great as that of compstatin.It is noted that certain modifications known to reduce or eliminatecomplement inhibiting activity and may be explicitly excluded from anyembodiment of the invention. The IC₅₀ of compstatin has been measured as12 μM using an alternative pathway-mediated erythrocyte lysis assay(WO2004/026328). It will be appreciated that the precise IC₅₀ valuemeasured for a given compstatin analog will vary with experimentalconditions (e.g., the serum concentration used in the assay).Comparative values, e.g., obtained from experiments in which IC₅₀ isdetermined for multiple different compounds under substantiallyidentical conditions, are of use. In one embodiment, the IC₅₀ of thecompstatin analog is no more than the IC₅₀ of compstatin. In certainembodiments of the invention the activity of the compstatin analog isbetween 2 and 99 times that of compstatin (i.e., the analog has an IC₅₀that is less than the IC₅₀ of compstatin by a factor of between 2 and99). For example, the activity may be between 10 and 50 times as greatas that of compstatin, or between 50 and 99 times as great as that ofcompstatin. In certain embodiments of the invention the activity of thecompstatin analog is between 99 and 264 times that of compstatin. Forexample, the activity may be 100, 110, 120, 130, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, or 264 times as great asthat of compstatin. In certain embodiments the activity is between 250and 300, 300 and 350, 350 and 400, or 400 and 500 times as great as thatof compstatin. The invention further contemplates compstatin analogshaving activities between 500 and 1000 times that of compstatin, ormore, e.g., between 1000 and 2000 times that of compstatin, or more. Incertain embodiments the IC₅₀ of the compstatin analog is between about0.2 μM and about 0.5 μM. In certain embodiments the IC₅₀ of thecompstatin analog is between about 0.1 μM and about 0.2 μM. In certainembodiments the IC₅₀ of the compstatin analog is between about 0.05 μMand about 0.1 μM. In certain embodiments the IC₅₀ of the compstatinanalog is between about 0.001 μM and about 0.05 μM.

The K_(d) of compstatin binding to C3 can be measured using isothermaltitration calorimetry (Katragadda, et al., J. Biol. Chem., 279(53),54987-54995, 2004). Binding affinity of a variety of compstatin analogsfor C3 has been correlated with their activity, with a lower K_(d)indicating a higher binding affinity, as recognized in the art. A linearcorrelation between binding affinity and activity was shown for certainanalogs tested (Katragadda, 2004, supra; Katragadda 2006, supra). Incertain embodiments of the invention the compstatin analog binds to C3with a K_(d) of between 0.1 μM and 1.0 μM, between 0.05 μM and 0.1 μM,between 0.025 μM and 0.05 μM, between 0.015 μM and 0.025 μM, between0.01 μM and 0.015 μM, or between 0.001 μM and 0.01 μM.

Compounds “designed or identified based on compstatin” include, but arenot limited to, compounds that comprise an amino acid chain whosesequence is obtained by (i) modifying the sequence of compstatin (e.g.,replacing one or more amino acids of the sequence of compstatin with adifferent amino acid or amino acid analog, inserting one or more aminoacids or amino acid analogs into the sequence of compstatin, or deletingone or more amino acids from the sequence of compstatin); (ii) selectionfrom a phage display peptide library in which one or more amino acids ofcompstatin is randomized, and optionally further modified according tomethod (i); or (iii) identified by screening for compounds that competewith compstatin or any analog thereof obtained by methods (i) or (ii)for binding to C3 or a fragment thereof. Many useful compstatin analogscomprise a hydrophobic cluster, a β-turn, and a disulfide bridge.

In certain embodiments of the invention the sequence of the compstatinanalog comprises or consists essentially of a sequence that is obtainedby making 1, 2, 3, or 4 substitutions in the sequence of compstatin,i.e., 1, 2, 3, or 4 amino acids in the sequence of compstatin isreplaced by a different standard amino acid or by a non-standard aminoacid. In certain embodiments of the invention the amino acid at position4 is altered. In certain embodiments of the invention the amino acid atposition 9 is altered. In certain embodiments of the invention the aminoacids at positions 4 and 9 are altered. In certain embodiments of theinvention only the amino acids at positions 4 and 9 are altered. Incertain embodiments of the invention the amino acid at position 4 or 9is altered, or in certain embodiments both amino acids 4 and 9 arealtered, and in addition up to 2 amino acids located at positionsselected from 1, 7, 10, 11, and 13 are altered. In certain embodimentsof the invention the amino acids at positions 4, 7, and 9 are altered.In certain embodiments of the invention amino acids at position 2, 12,or both are altered, provided that the alteration preserves the abilityof the compound to be cyclized. Such alteration(s) at positions 2 and/or12 may be in addition to the alteration(s) at position 1, 4, 7, 9, 10,11, and/or 13. Optionally the sequence of any of the compstatin analogswhose sequence is obtained by replacing one or more amino acids ofcompstatin sequence further includes up to 1, 2, or 3 additional aminoacids at the C-terminus. In one embodiment, the additional amino acid isGly. Optionally the sequence of any of the compstatin analogs whosesequence is obtained by replacing one or more amino acids of compstatinsequence further includes up to 5, or up to 10 additional amino acids atthe C-terminus. It should be understood that compstatin analogs may haveany one or more of the characteristics or features of the variousembodiments described herein, and characteristics or features of anyembodiment may additionally characterize any other embodiment describedherein, unless otherwise stated or evident from the context. In certainembodiments of the invention the sequence of the compstatin analogcomprises or consists essentially of a sequence identical to that ofcompstatin except at positions corresponding to positions 4 and 9 in thesequence of compstatin.

Compstatin and certain compstatin analogs having somewhat greateractivity than compstatin contain only standard amino acids (“standardamino acids” are glycine, leucine, isoleucine, valine, alanine,phenylalanine, tyrosine, tryptophan, aspartic acid, asparagine, glutamicacid, glutamine, cysteine, methionine, arginine, lysine, proline,serine, threonine and histidine). Certain compstatin analogs havingimproved activity incorporate one or more non-standard amino acids.Useful non-standard amino acids include singly and multiply halogenated(e.g., fluorinated) amino acids, D-amino acids, homo-amino acids,N-alkyl amino acids, dehydroamino acids, aromatic amino acids (otherthan phenylalanine, tyrosine and tryptophan), ortho-, meta- orpara-aminobenzoic acid, phospho-amino acids, methoxylated amino acids,and a,a-disubstituted amino acids. In certain embodiments of theinvention, a compstatin analog is designed by replacing one or moreL-amino acids in a compstatin analog described elsewhere herein with thecorresponding D-amino acid. Such compounds and methods of use thereofare an aspect of the invention. Exemplary non-standard amino acids ofuse include 2-naphthylalanine (2-NaI), 1-naphthylalanine (1-NaI),2-indanylglycine carboxylic acid (2Igl), dihydrotrpytophan (Dht),4-benzoyl-L-phenylalanine (Bpa), 2-α-aminobutyric acid (2-Abu),3-α-aminobutyric acid (3-Abu), 4-α-aminobutyric acid (4-Abu),cyclohexylalanine (Cha), homocyclohexylalanine (hCha),4-fluoro-L-tryptophan (4fW), 5-fluoro-L-tryptophan (5fW),6-fluoro-L-tryptophan (6fW), 4-hydroxy-L-tryptophan (4OH-W),5-hydroxy-L-tryptophan (5OH-W), 6-hydroxy-L-tryptophan (6OH-W),1-methyl-L-tryptophan (1MeW), 4-methyl-L-tryptophan (4MeW),5-methyl-L-tryptophan (SMeW), 7-aza-L-tryptophan (7aW),α-methyl-L-tryptophan (αMeW), β-methyl-L-tryptophan (βMeW),N-methyl-L-tryptophan (NMeW), ornithine (orn), citrulline, norleucine,γ-glutamic acid, etc.

In certain embodiments of the invention the compstatin analog comprisesone or more Trp analogs (e.g., at position 4 and/or 7 relative to thesequence of compstatin). Exemplary Trp analogs are mentioned above. Seealso Beene, et. al. Biochemistry 41: 10262-10269, 2002 (describing,inter alia, singly- and multiply-halogenated Trp analogs); Babitzke &Yanofsky, J. Biol. Chem. 270: 12452-12456, 1995 (describing, inter alia,methylated and halogenated Trp and other Trp and indole analogs); andU.S. Pat. Nos. 6,214,790, 6,169,057, 5,776,970, 4,870,097, 4,576,750 and4,299,838. Other Trp analogs include variants that are substituted(e.g., by a methyl group) at the α or β carbon and, optionally, also atone or more positions of the indole ring. Amino acids comprising two ormore aromatic rings, including substituted, unsubstituted, oralternatively substituted variants thereof, are of interest as Trpanalogs. In certain embodiments of the invention the Trp analog, e.g.,at position 4, is 5-methoxy, 5-methyl-, 1-methyl-, or1-formyl-tryptophan. In certain embodiments of the invention a Trpanalog (e.g., at position 4) comprising a 1-alkyl substituent, e.g., alower alkyl (e.g., C₁-C₅) substituent is used. In certain embodiments,N(α) methyl tryptophan or 5-methyltryptophan is used. In someembodiments, an analog comprising a 1-alkanyol substituent, e.g., alower alkanoyl (e.g., C₁-C₅) is used. Examples include1-acetyl-L-tryptophan and L-β-tryptophan.

In certain embodiments the Trp analog has increased hydrophobiccharacter relative to Trp. For example, the indole ring may besubstituted by one or more alkyl (e.g., methyl) groups. In certainembodiments the Trp analog participates in a hydrophobic interactionwith C3. Such a Trp analog may be located, e.g., at position 4 relativeto the sequence of compstatin. In certain embodiments the Trp analogcomprises a substituted or unsubstituted bicyclic aromatic ringcomponent or two or more substituted or unsubstituted monocyclicaromatic ring components.

In certain embodiments the Trp analog has increased propensity to formhydrogen bonds with C3 relative to Trp but does not have increasedhydrophobic character relative to Trp. The Trp analog may have increasedpolarity relative to Trp and/or an increased ability to participate inan electrostatic interaction with a hydrogen bond donor on C3. Certainexemplary Trp analogs with an increased hydrogen bond forming charactercomprise an electronegative substituent on the indole ring. Such a Trpanalog may be located, e.g., at position 7 relative to the sequence ofcompstatin.

In certain embodiments of the invention the compstatin analog comprisesone or more Ala analogs (e.g., at position 9 relative to the sequence ofcompstatin), e.g., Ala analogs that are identical to Ala except thatthey include one or more CH₂ groups in the side chain. In certainembodiments the Ala analog is an unbranched single methyl amino acidsuch as 2-Abu. In certain embodiments of the invention the compstatinanalog comprises one or more Trp analogs (e.g., at position 4 and/or 7relative to the sequence of compstatin) and an Ala analog (e.g., atposition 9 relative to the sequence of compstatin).

In certain embodiments of the invention the compstatin analog is acompound that comprises a peptide that has a sequence of(X′aa)_(n)-Gln-Asp-Xaa-Gly-(X″aa)_(m), (SEQ ID NO: 2) wherein each X′aaand each X″aa is an independently selected amino acid or amino acidanalog, wherein Xaa is Trp or an analog of Trp, and wherein n>1 and m>1and n+m is between 5 and 21. The peptide has a core sequence ofGln-Asp-Xaa-Gly, where Xaa is Trp or an analog of Trp, e.g., an analogof Trp having increased propensity to form hydrogen bonds with an H-bonddonor relative to Trp but, in certain embodiments, not having increasedhydrophobic character relative to Trp. For example, the analog may beone in which the indole ring of Trp is substituted with anelectronegative moiety, e.g., a halogen such as fluorine. In oneembodiment Xaa is 5-fluorotryptophan. Absent evidence to the contrary,one of skill in the art would recognize that any non-naturally occurringpeptide whose sequence comprises this core sequence and that inhibitscomplement activation and/or binds to C3 will have been designed basedon the sequence of compstatin. In an alternative embodiment Xaa is anamino acid or amino acid analog other than a Trp analog that allows theGln-Asp-Xaa-Gly peptide to form a β-turn.

In certain embodiments of the invention the peptide has a core sequenceof X′aa-Gln-Asp-Xaa-Gly (SEQ ID NO: 3), where X′aa and Xaa are selectedfrom Trp and analogs of Trp. In certain embodiments of the invention thepeptide has a core sequence of X′aa-Gln-Asp-Xaa-Gly (SEQ ID NO: 3),where X′aa and Xaa are selected from Trp, analogs of Trp, and otheramino acids or amino acid analogs comprising at least one aromatic ring.In certain embodiments of the invention the core sequence forms a β-turnin the context of the peptide. The β-turn may be flexible, allowing thepeptide to assume two or more conformations as assessed for example,using nuclear magnetic resonance (NMR). In certain embodiments X′aa isan analog of Trp that comprises a substituted or unsubstituted bicyclicaromatic ring component or two or more substituted or unsubstitutedmonocyclic aromatic ring components. In certain embodiments of theinvention X′aa is selected from the group consisting of2-napthylalanine, 1-napthylalanine, 2-indanylglycine carboxylic acid,dihydrotryptophan, and benzoylphenylalanine. In certain embodiments ofthe invention X′aa is an analog of Trp that has increased hydrophobiccharacter relative to Trp. For example, X′aa may be 1-methyltryptophan.In certain embodiments of the invention Xaa is an analog of Trp that hasincreased propensity to form hydrogen bonds relative to Trp but, incertain embodiments, not having increased hydrophobic character relativeto Trp. In certain embodiments of the invention the analog of Trp thathas increased propensity to form hydrogen bonds relative to Trpcomprises a modification on the indole ring of Trp, e.g., at position 5,such as a substitution of a halogen atom for an H atom at position 5.For example, Xaa may be 5-fluorotryptophan.

In certain embodiments of the invention the peptide has a core sequenceof X′aa-Gln-Asp-Xaa-Gly-X″aa (SEQ ID NO: 4), where X′aa and Xaa are eachindependently selected from Trp and analogs of Trp and X″aa is selectedfrom His, Ala, analogs of Ala, Phe, and Trp. In certain embodiments ofthe invention X′aa is an analog of Trp that has increased hydrophobiccharacter relative to Trp, such as 1-methyltryptophan or another Trpanalog having an alkyl substituent on the indole ring (e.g., at position1, 4, 5, or 6). In certain embodiments X′aa is an analog of Trp thatcomprises a substituted or unsubstituted bicyclic aromatic ringcomponent or two or more substituted or unsubstituted monocyclicaromatic ring components. In certain embodiments of the invention X′aais selected from the group consisting of 2-napthylalanine,1-napthylalanine, 2-indanylglycine carboxylic acid, dihydrotryptophan,and benzoylphenylalanine. In certain embodiments of the invention Xaa isan analog of Trp that has increased propensity to form hydrogen bondswith C3 relative to Trp but, in certain embodiments, not havingincreased hydrophobic character relative to Trp. In certain embodimentsof the invention the analog of Trp that has increased propensity to formhydrogen bonds relative to Trp comprises a modification on the indolering of Trp, e.g., at position 5, such as a substitution of a halogenatom for an H atom at position 5. For example, Xaa may be5-fluorotryptophan. In certain embodiments X″aa is Ala or an analog ofAla such as Abu or another unbranched single methyl amino acid. Incertain embodiments of the invention the peptide has a core sequence ofX′aa-Gln-Asp-Xaa-Gly-X″aa (SEQ ID NO: 4), where X′aa and Xaa are eachindependently selected from Trp, analogs of Trp, and amino acids oramino acid analogs comprising at least one aromatic side chain, and X″aais selected from His, Ala, analogs of Ala, Phe, and Trp. In certainembodiments X″aa is selected from analogs of Trp, aromatic amino acids,and aromatic amino acid analogs.

In certain preferred embodiments of the invention the peptide is cyclic.The peptide may be cyclized via a bond between any two amino acids, oneof which is (X′aa)_(n) and the other of which is located within(X″aa)_(m). In certain embodiments the cyclic portion of the peptide isbetween 9 and 15 amino acids in length, e.g., 10-12 amino acids inlength. In certain embodiments the cyclic portion of the peptide is 11amino acids in length, with a bond (e.g., a disulfide bond) betweenamino acids at positions 2 and 12. For example, the peptide may be 13amino acids long, with a bond between amino acids at positions 2 and 12resulting in a cyclic portion 11 amino acids in length.

In certain embodiments the peptide comprises or consists of the sequenceX′aa1-X′aa2-X′aa3-X′aa4-Gln-Asp-Xaa-Gly-X″aa1-X″aa2-X″aa3-X″aa4-X″aa5(SEQ ID NO: 5). In certain embodiments X′aa4 and Xaa are selected fromTrp and analogs of Trp, and X′aa1, X′aa2, X′aa3, X″aa1, X″aa2, X″aa3,X″aa4, and X″aa5 are independently selected from among amino acids andamino acid analogs. In certain embodiments X′aa4 and Xaa are selectedfrom aromatic amino acids and aromatic amino acid analogs. Any one ormore of X′aa1, X′aa2, X′aa3, X″aa1, X″aa2, X″aa3, X″aa4, and X″aa5 maybe identical to the amino acid at the corresponding position incompstatin. In one embodiment, X″aa1 is Ala or a single methylunbranched amino acid. The peptide may be cyclized via a covalent bondbetween (i) X′aa1, X′aa2, or X′aa3; and (ii) X″aa2, X″aa3, X″aa4 orX″aa5. In one embodiment the peptide is cyclized via a covalent bondbetween X′aa2 and X″aa4. In one embodiment the covalently bound aminoacid are each Cys and the covalent bond is a disulfide (S—S) bond. Inother embodiments the covalent bond is a C—C, C—O, C—S, or C—N bond. Incertain embodiments one of the covalently bound residues is an aminoacid or amino acid analog having a side chain that comprises a primaryor secondary amine, the other covalently bound residue is an amino acidor amino acid analog having a side chain that comprises a carboxylicacid group, and the covalent bond is an amide bond. Amino acids or aminoacid analogs having a side chain that comprises a primary or secondaryamine include lysine and diaminocarboxylic acids of general structureNH₂(CH₂)_(n)CH(NH₂)COOH such as 2,3-diaminopropionic acid (dapa),2,4-diaminobutyric acid (daba), and ornithine (orn), wherein n=1 (dapa),2 (daba), and 3 (orn), respectively. Examples of amino acids having aside chain that comprises a carboxylic acid group include dicarboxylicamino acids such as glutamic acid and aspartic acid. Analogs such asbeta-hydroxy-L-glutamic acid may also be used.

In certain embodiments, the compstatin analog is a compound thatcomprises a peptide having a sequence:

(SEQ ID NO: 6) Xaa1-Cys-Val-Xaa2-Gln-Asp-Xaa2*-Gly*-Xaa3-His-Arg-Cys-Xaa4;wherein:

-   Xaa1 is Ile, Val, Leu, B¹-Ile, B¹-Val, B¹-Leu or a dipeptide    comprising Gly-Ile or B¹-Gly-Ile, and B¹ represents a first blocking    moiety;-   Xaa2 and Xaa2* are independently selected from Trp and analogs of    Trp;-   Xaa3 is His, Ala or an analog of Ala, Phe, Trp, or an analog of Trp;-   Xaa4 is L-Thr, D-Thr, Ile, Val, Gly, a dipeptide selected from    Thr-Ala and Thr-Asn, or a tripeptide comprising Thr-Ala-Asn, wherein    a carboxy terminal —OH of any of the L-Thr, D-Thr, Ile, Val, Gly,    Ala, or Asn optionally is replaced by a second blocking moiety B²;    and-   the two Cys residues are joined by a disulfide bond. In some    embodiments, Xaa4 is Leu, Nle, His, or Phe or a dipeptide selected    from Xaa5-Ala and Xaa5-Asn, or a tripeptide Xaa5-Ala-Asn, wherein    Xaa5 is selected from Leu, Nle, His or Phe, and wherein a carboxy    terminal —OH of any of the L-Thr, D-Thr, Ile, Val, Gly, Leu, Nle,    His, Phe, Ala, or Asn optionally is replaced by a second blocking    moiety B²; and the two Cys residues are joined by a disulfide bond.

In other embodiments Xaa1 is absent or is any amino acid or amino acidanalog, and Xaa2, Xaa2*, Xaa3, and Xaa4 are as defined above. If Xaa1 isabsent, the N-terminal Cys residue may have a blocking moiety B¹attached thereto.

In another embodiment, Xaa4 is any amino acid or amino acid analog andXaa1, Xaa2, Xaa2*, and Xaa3 are as defined above. In another embodimentXaa4 is a dipeptide selected from the group consisting of: Thr-Ala andThr-Asn, wherein the carboxy terminal —OH or the Ala or Asn isoptionally replaced by a second blocking moiety B².

In any of the embodiments of the compstatin analog of SEQ ID NO: 6, Xaa2may be Trp.

In any of the embodiments of the compstatin analog of SEQ ID NO: 6, Xaa2may be an analog of Trp comprising a substituted or unsubstitutedbicyclic aromatic ring component or two or more substituted orunsubstituted monocyclic aromatic ring components. For example, theanalog of Trp may be selected from 2-naphthylalanine (2-NaI),1-naphthylalanine (1-NaI), 2-indanylglycine carboxylic acid (Igl),dihydrotrpytophan (Dht), and 4-benzoyl-L-phenylalanine.

In any of the embodiments of the compstatin analog of SEQ ID NO: 6, Xaa2may be an analog of Trp having increased hydrophobic character relativeto Trp. For example, the analog of Trp may be selected from1-methyltryptophan, 4-methyltryptophan, 5-methyltryptophan, and6-methyltryptophan. In one embodiment, the analog of Trp is1-methyltryptophan. In one embodiment, Xaa2 is 1-methyltryptophan, Xaa2*is Trp, Xaa3 is Ala, and the other amino acids are identical to those ofcompstatin.

In any of the embodiments of the compstatin analog of SEQ ID NO: 6,Xaa2* may be an analog of Trp such as an analog of Trp having increasedhydrogen bond forming propensity with C3 relative to Trp, which, incertain embodiments, does not have increased hydrophobic characterrelative to Trp. In certain embodiments the analog of Trp comprises anelectronegative substituent on the indole ring. For example, the analogof Trp may be selected from 5-fluorotryptophan and 6-fluorotryptophan.

In certain embodiments of the invention Xaa2 is Trp and Xaa2* is ananalog of Trp having increased hydrogen bond forming propensity with C3relative to Trp which, in certain embodiments, does not have increasedhydrophobic character relative to Trp. In certain embodiments of thecompstatin analog of SEQ ID NO: 6, Xaa2 is analog of Trp havingincreased hydrophobic character relative to Trp such as an analog of Trpselected from 1-methyltryptophan, 4-methyltryptophan,5-methyltryptophan, and 6-methyltryptophan, and and Xaa2* is an analogof Trp having increased hydrogen bond forming propensity with C3relative to Trp which, in certain embodiments, does not have increasedhydrophobic character relative to Trp. For example, in one embodimentXaa2 is methyltryptophan and Xaa2* is 5-fluorotryptophan.

In certain of the afore-mentioned embodiments, Xaa3 is Ala. In certainof the afore-mentioned embodiments Xaa3 is a single methyl unbranchedamino acid, e.g., Abu.

The invention further provides compstatin analogs of SEQ ID NO: 6, asdescribed above, wherein Xaa2 and Xaa2* are independently selected fromTrp, analogs of Trp, and other amino acids or amino acid analogs thatcomprise at least one aromatic ring, and Xaa3 is His, Ala or an analogof Ala, Phe, Trp, an analog of Trp, or another aromatic amino acid oraromatic amino acid analog.

In certain embodiments of the invention the blocking moiety present atthe N- or C-terminus of any of the compstatin analogs described hereinis any moiety that stabilizes a peptide against degradation that wouldotherwise occur in mammalian (e.g., human or non-human primate) blood orinterstitial fluid. For example, blocking moiety B¹ could be any moietythat alters the structure of the N-terminus of a peptide so as toinhibit cleavage of a peptide bond between the N-terminal amino acid ofthe peptide and the adjacent amino acid. Blocking moiety B² could be anymoiety that alters the structure of the C-terminus of a peptide so as toinhibit cleavage of a peptide bond between the C-terminal amino acid ofthe peptide and the adjacent amino acid. Any suitable blocking moietiesknown in the art could be used. In certain embodiments of the inventionblocking moiety B¹ comprises an acyl group (i.e., the portion of acarboxylic acid that remains following removal of the —OH group). Theacyl group typically comprises between 1 and 12 carbons, e.g., between 1and 6 carbons. For example, in certain embodiments of the inventionblocking moiety B¹ is selected from the group consisting of: formyl,acetyl, proprionyl, butyryl, isobutyryl, valeryl, isovaleryl, etc. Inone embodiment, the blocking moiety B¹ is an acetyl group, i.e., Xaa1 isAc-Ile, Ac-Val, Ac-Leu, or Ac-Gly-Ile.

In certain embodiments of the invention blocking moiety B² is a primaryor secondary amine (—NH₂ or —NHR¹, wherein R is an organic moiety suchas an alkyl group).

In certain embodiments of the invention blocking moiety B¹ is any moietythat neutralizes or reduces the negative charge that may otherwise bepresent at the N-terminus at physiological pH. In certain embodiments ofthe invention blocking moiety B² is any moiety that neutralizes orreduces the negative charge that may otherwise be present at theC-terminus at physiological pH.

In certain embodiments of the invention, the compstatin analog isacetylated or amidated at the N-terminus and/or C-terminus,respectively. A compstatin analog may be acetylated at the N-terminus,amidated at the C-terminus, and or both acetylated at the N-terminus andamidated at the C-terminus. In certain embodiments of the invention acompstatin analog comprises an alkyl or aryl group at the N-terminusrather than an acetyl group.

In certain embodiments, the compstatin analog is a compound thatcomprises a peptide having a sequence:

(SEQ ID NO: 7) Xaa1-Cys-Val-Xaa2-Gln-Asp-Xaa2*-Gly-Xaa3-His-Arg-Cys-Xaa4;wherein:

-   Xaa1 is Ile, Val, Leu, Ac-Ile, Ac-Val, Ac-Leu or a dipeptide    comprising Gly-Ile or Ac-Gly-Ile;-   Xaa2 and Xaa2* are independently selected from Trp and analogs of    Trp;-   Xaa3 is His, Ala or an analog of Ala, Phe, Trp, or an analog of Trp;-   Xaa4 is L-Thr, D-Thr, Ile, Val, Gly, a dipeptide selected from    Thr-Ala and Thr-Asn, or a tripeptide comprising Thr-Ala-Asn, wherein    a carboxy terminal —OH of any of L-Thr, D-Thr, Ile, Val, Gly, Ala,    or Asn optionally is replaced by —NH₂; and the two Cys residues are    joined by a disulfide bond. In some embodiments, Xaa4 is Leu, Nle,    His, or Phe or a depeptide selected from Xaa5-Ala and Xaa5-Asn, or a    tripeptide Xaa5-Ala-Asn, wherein Xaa5 is selected from Leu, Nle, His    or Phe, and wherein a carboxy terminal —OH of any of the L-Thr,    D-Thr, Ile, Val, Gly, Leu, Nle, His, Phe, Ala, or Asn optionally is    replaced by a second blocking moiety B2; and the two Cys residues    are joined by a disulfide bond.

In some embodiments, Xaa1, Xaa2, Xaa2*, Xaa3, and Xaa4 are as describedabove for the various embodiments of SEQ ID NO: 6. For example, incertain embodiments Xaa2* is Trp. In certain embodiments Xaa2 is ananalog of Trp having increased hydrophobic character relative to Trp,e.g., 1-methyltryptophan. In certain embodiments Xaa3 is Ala. In certainembodiments Xaa3 is a single methyl unbranched amino acid.

In certain embodiments of the invention Xaa1 is Ile and Xaa4 is L-Thr.

In certain embodiments of the invention Xaa1 is Ile, Xaa2* is Trp, andXaa4 is L-Thr.

The invention further provides compstatin analogs of SEQ ID NO: 7, asdescribed above, wherein Xaa2 and Xaa2* are independently selected fromTrp, analogs of Trp, other amino acids or aromatic amino acid analogs,and Xaa3 is His, Ala or an analog of Ala, Phe, Trp, an analog of Trp, oranother aromatic amino acid or aromatic amino acid analog.

In certain embodiments of any of the compstatin analogs describedherein, an analog of Phe is used rather than Phe.

Table 1 provides a non-limiting list of compstatin analogs useful in thepresent invention. The analogs are referred to in abbreviated form inthe left column by indicating specific modifications at designatedpositions (1-13) as compared to the parent peptide, compstatin.Consistent with usage in the art, “compstatin” as used herein, and theactivities of compstatin analogs described herein relative to that ofcompstatin, refer to the compstatin peptide amidated at the C-terminus.Unless otherwise indicated, peptides in Table 1 are amidated at theC-terminus. Bold text is used to indicate certain modifications.Activity relative to compstatin is based on published data and assaysdescribed therein (WO2004/026328, WO2007044668, Mallik, 2005;Katragadda, 2006). Where multiple publications reporting an activitywere consulted, the more recently published value is used, and it willbe recognized that values may be adjusted in the case of differencesbetween assays. It will also be appreciated that in certain embodimentsof the invention the peptides listed in Table 1 are cyclized via adisulfide bond between the two Cys residues when used in the therapeuticcompositions and methods of the invention. Alternate means for cyclizingthe peptides are also within the scope of the invention. As noted above,in various embodiments of the invention one or more amino acid(s) of acompstatin analog (e.g., any of the compstatin analogs disclosed herein)can be an N-alkyl amino acid (e.g., an N-methyl amino acid). Forexample, and without limitation, at least one amino acid within thecyclic portion of the peptide, at least one amino acid N-terminal to thecyclic portion, and/or at least one amino acid C-terminal to the cyclicportion may be an N-alkyl amino acid, e.g., an N-methyl amino acid. Insome embodiments of the invention, for example, a compstatin analogcomprises an N-methyl glycine, e.g., at the position corresponding toposition 8 of compstatin and/or at the position corresponding toposition 13 of compstatin. In some embodiments, one or more of thecompstatin analogs in Table 1 contains at least one N-methyl glycine,e.g., at the position corresponding to position 8 of compstatin and/orat the position corresponding to position 13 of compstatin.

TABLE 1 SEQ ID Activity over Peptide Sequence NO: compstatin CompstatinH-ICVVQDWGHHRCT-CONH2  8 * Ac-compstatin Ac-ICVVQDWGHHRCT-CONH2  93xmore Ac-V4Y/H9A Ac-ICV Y QDWG A HRCT-CONH2 10 14xmore Ac-V4W/H9A-OHAc-ICV W QDWG A HRCT-COOH 11 27xmore Ac-V4W/H9A Ac-ICV W QDWG AHRCT-CONH2 12 45xmore Ac-V4W/H9A/T13dT-OH Ac-ICV W QDWG A HRC dT -COOH13 55xmore Ac-V4(2-Nal)/H9A Ac-ICV(2-Nal)QDWG A HRCT-CONH2 14 99xmoreAc V4(2-Nal)/H9A-OH Ac-ICV(2-Nal)QDWG A HRCT-COOH 15 38xmoreAc V4(1-Nal)/H9A-OH Ac-ICV(1-Nal)QDWG A HRCT-COOH 16 30xmoreAc-V42Igl/H9A Ac-ICV(2-Igl)QDWG A HRCT-CONH2 17 39xmore Ac-V42Igl/H9A-OHAc-ICV(2-1d1)QDWG A HRCT-COOH 18 37xmore Ac-V4Dht/H9A-OH Ac-ICV DhtQDWGAHRCT-COOH 19 5xmore Ac-V4(Bpa)/H9A-OH Ac-ICV(Bpa)QDWG A HRCT-COOH20 49xmore Ac-V4(Bpa)/H9A Ac-ICV(Bpa)QDWG A HRCT-CONH2 21 86xmoreAc-V4(Bta)/H9A-OH Ac-ICV(Bta)QDWG A HRCT-COOH 22 65xmore Ac-V4(Bta)/H9AAc-ICV(Bta)QDWG A HRCT-CONH2 23 64xmore Ac-V4W/H9(2-Abu) Ac-ICV WQDWG(2-Abu)HRCT-CONH2 24 64xmore +G/V4W/H9A +AN-OH H- G ICV W QDWG AHRCTA N -COOH 25 38xmore Ac-V4(5fW)/H9A Ac-ICV(5fW)QDWG A HRCT-CONH2 2631xmore Ac-V4(5-MeW)/H9A Ac-ICV(5-methl-W)QDWG A HRCT-CONH2 27 67xmoreAc-V4(1-MeW)/H9A Ac-ICV(1-methl-W)QDWG A HRCT-CONH2 28 264xmoreAc-V4W/W7(5fW)/H9A Ac-ICV W QD(5fW)G A HRCT-CONH2 29 121xmoreAc-V4(5fW)/W7(5fW)/H9A Ac-ICV(5fW)QD(5fW)G A HRCT-CONH2 30 NAAc-V4(5-MeW)/W7(5fW)H9A Ac-ICV(5-methyl-W)QD(5fW)G A HRCT- 31 NA CONH2Ac-V4(1MeW)/W7(5fW)/H9A Ac-ICV(1-methyl-W)QD(5fW)G A HRCT- 32 264xmoreCONH2 +G/V4(6fW)/W7(6fW)H9A + N- H-GICV(6fW)QD(6fW)G A HRCT N -COOH 33126xmore OH Ac-V4(1-formyl-W)/H9A Ac-ICV(1-forml-W)QDWG A HRCT-CONH2 34264xmore Ac-V4(5-methoxy-W)/H9A Ac-ICV(1-methyoxy-W)QDWG A HRCT- 3576xmore CONH2 G/V4(5f-W)/W7(5fW)/H9A + N- H-GICV(5fW)QD(5fW)G A HRCT N-COOH 36 112xmore OH NA = not available

In certain embodiments of the compositions and methods of the inventionthe compstatin analog has a sequence selected from sequences 9-36. Incertain embodiments of the compositions and methods of the invention thecompstatin analog has a sequence selected from SEQ ID NOs: 14, 21, 28,29, 32, 33, 34, and 36. In certain embodiments of the compositionsand/or methods of the invention the compstatin analog has a sequenceselected from SEQ ID NOs: 30 and 31. In one embodiment of thecompositions and methods of the invention the compstatin analog has asequence of SEQ ID NO: 28. In one embodiment of the compositions andmethods of the invention the compstatin analog has a sequence of SEQ IDNO: 32. In one embodiment of the compositions and methods of theinvention the compstatin analog has a sequence of SEQ ID NO: 34. In oneembodiment of the compositions and methods of the invention thecompstatin analog has a sequence of SEQ ID NO: 36.

In certain embodiments of the compositions and methods of the inventionthe compstatin analog has a sequence as set forth in Table 1, but wherethe Ac-group is replaced by an alternate blocking moiety B¹, asdescribed above. In some embodiments the —NH₂ group is replaced by analternate blocking moiety B², as described above.

In one embodiment, the compstatin analog binds to substantially the sameregion of the β chain of human C3 as does compstatin. In one embodimentthe compstatin analog is a compound that binds to a fragment of theC-terminal portion of the β chain of human C3 having a molecular weightof about 40 kDa to which compstatin binds (Soulika, A. M., et al., Mol.Immunol., 35:160, 1998; Soulika, A. M., et al., Mol. Immunol.43(12):2023-9, 2006). In certain embodiments the compstatin analog is acompound that binds to the binding site of compstatin as determined in acompstatin-C3 structure, e.g., a crystal structure or NMR-derived 3Dstructure. In certain embodiments the compstatin analog is a compoundthat could substitute for compstatin in a compstatin-C3 structure andwould form substantially the same intermolecular contacts with C3 ascompstatin. In certain embodiments the compstatin analog is a compoundthat binds to the binding site of a peptide having a sequence set forthin Table 1, e.g., SEQ ID NO: 14, 21, 28, 29, 32, 33, 34, or 36 in apeptide-C3 structure, e.g., a crystal structure. In certain embodimentsthe compstatin analog is a compound that binds to the binding site of apeptide having SEQ ID NO: 30 or 31 in a peptide-C3 structure, e.g., acrystal structure. In certain embodiments the compstatin analog is acompound that could substitute for the peptide of SEQ ID NO: 9-36, e.g.,a compound that could substitute for the peptide of SEQ ID NO: 14, 21,28, 29, 32, 33, 34, or 36 in a peptide-C3 structure and would formsubstantially the same intermolecular contacts with C3 as the peptide.In certain embodiments the compstatin analog is a compound that couldsubstitute for the peptide of SEQ ID NO: 30 or 31 in a peptide-C3structure and would form substantially the same intermolecular contactswith C3 as the peptide.

One of ordinary skill in the art will readily be able to determinewhether a compstatin analog binds to a fragment of the C-terminalportion of the β chain of C3 using routine experimental methods. Forexample, one of skill in the art could synthesize a photocrosslinkableversion of the compstatin analog by including a photo-crosslinking aminoacid such as p-benzoyl-L-phenylalanine (Bpa) in the compound, e.g., atthe C-terminus of the sequence (Soulika, A. M., et al, supra).Optionally additional amino acids, e.g., an epitope tag such as a FLAGtag or an HA tag could be included to facilitate detection of thecompound, e.g., by Western blotting. The compstatin analog is incubatedwith the fragment and crosslinking is initiated. Colocalization of thecompstatin analog and the C3 fragment indicates binding. Surface plasmonresonance may also be used to determine whether a compstatin analogbinds to the compstatin binding site on C3 or a fragment thereof and/orto measure binding affinity. A competition experiment, e.g., whereinbinding of a compstatin analog to the compstatin binding site on C3 or afragment thereof interferes with binding of compstatin, may be used. Oneof skill in the art would be able to use molecular modeling softwareprograms to predict whether a compound would form substantially the sameintermolecular contacts with C3 as would compstatin or a peptide havingthe sequence of any of the peptides in Table 1, e.g., SEQ ID NO: 14, 21,28, 29, 32, 33, 34, or 36, or in some embodiments SEQ ID NO: 30 or 31.

Compstatin analogs may be prepared by various synthetic methods ofpeptide synthesis known in the art via condensation of amino acidresidues, e.g., in accordance with conventional peptide synthesismethods, may be prepared by expression in vitro or in living cells fromappropriate nucleic acid sequences encoding them using methods known inthe art. For example, peptides may be synthesized using standardsolid-phase methodologies as described in Malik, supra, Katragadda,supra, WO2004026328, and/or WO2007062249. Potentially reactive moietiessuch as amino and carboxyl groups, reactive functional groups, etc., maybe protected and subsequently deprotected using various protectinggroups and methodologies known in the art. See, e.g., “Protective Groupsin Organic Synthesis”, 3^(rd) ed. Greene, T. W. and Wuts, P. G., Eds.,John Wiley & Sons, New York: 1999. Peptides may be purified usingstandard approaches such as reversed-phase HPLC. Separation ofdiasteriomeric peptides, if desired, may be performed using knownmethods such as reversed-phase HPLC. Preparations may be lyophilized, ifdesired, and subsequently dissolved in a suitable solvent, e.g., water.The pH of the resulting solution may be adjusted, e.g. to physiologicalpH, using a base such as NaOH. Peptide preparations may be characterizedby mass spectrometry if desired, e.g., to confirm mass and/or disulfidebond formation. See, e.g., Mallik, 2005, and Katragadda, 2006.

A compstatin analog can be modified by addition of a molecule such aspolyethylene glycol (PEG) or similar molecules to stabilize thecompound, reduce its immunogenicity, increase its lifetime in the body,increase or decrease its solubility, and/or increase its resistance todegradation. Methods for pegylation are well known in the art (Veronese,F. M. & Harris, Adv. Drug Deliv. Rev. 54, 453-456, 2002; Davis, F. F.,Adv. Drug Deliv. Rev. 54, 457-458, 2002); Hinds, K. D. & Kim, S. W. Adv.Drug Deliv. Rev. 54, 505-530 (2002; Roberts, M. J., Bentley, M. D. &Harris, J. M. Adv. Drug Deliv. Rev. 54, 459-476; 2002); Wang, Y. S. etal. Adv. Drug Deliv. Rev. 54, 547-570, 2002). A wide variety of polymerssuch as PEGs and modified PEGs, including derivatized PEGs to whichpolypeptides can conveniently be attached are described in NektarAdvanced Pegylation 2005-2006 Product Catalog, Nektar Therapeutics, SanCarlos, Calif., which also provides details of appropriate conjugationprocedures. In another embodiment a compstatin analog is fused to the Fcdomain of an immunoglobulin or a portion thereof. In some otherembodiments a compstatin analog is conjugated to an albumin moiety(e.g., human serum albumin or a portion thereof) or to an albuminbinding peptide. Thus in some embodiments a compstatin analog ismodified with one or more polypeptide or non-polypeptide components,e.g., the compstatin analog is pegylated or conjugated to anothermoiety. In some embodiments the component is not the Fc domain of animmunoglobulin or a portion thereof. A compstatin analog can be providedas a multimer or as part of a supramolecular complex, which can includeeither a single molecular species or multiple different species (e.g.,multiple different analogs).

In some embodiments, a PEG or other moiety has an average molecularweight of at least 10 kD, e.g., at least 20 kD, 30 kD, 40 kD, 50 kD, 60kD, 70 kD, 80 kD, 90kD, 100 kD, 110 kD, 120 kD, 130 kD, 140 kD, 150 kD,or more in various embodiments. For example, an average molecular weightmay be between 10 kD and 100 kD, e.g., about 10 kD, 20 kD, 30 kD, 40 kD,50 kD, 60 kD, 70 kD, 75 kD, 80 kD, 90kD, or 100 kD.

In some embodiments, a compstatin analog, e.g., modified with PEG orother moiety, has a half-life at least 3, 5, 7, 10, 20, 30, 50, 75,100-fold or more as great as that of a compstatin analog having the samepeptide sequence but lacking the moiety. For example, a half-life may bebetween 3 and 100-fold as great as that of a compstatin analog havingthe same peptide sequence but lacking the moiety, e.g., between 3 and50-fold as great, between 50 and 100-fold as great, etc.

In some embodiments, a compstatin analog, e.g., modified with PEG orother moiety, has a plasma half-life of at least 1, 2, 3, 4, 5, 6, 7,10, 14, 21, or 28 days. For example, a compstatin analog, e.g., modifiedwith PEG or other moiety, may have a plasma half-life of between 1 dayand 28 days, e.g., between 1 day and 4 days, between 4 days and 7 days,etc.

It will be appreciated that a variety of approaches to determiningpharmacokinetic (PK) parameters such as half-life can be used. Anappropriate method can be selected by one of ordinary skill in the art.In general, half-life can be determined by a method comprising:administering one or more doses of the compound to subjects, obtainingblood samples from the subject at various times after administration,measuring the concentration of the compound in said samples, andcalculating a half-life based at least in part on said measurements. Forexample, in some embodiments, samples may be obtained at times 0(pre-dose), 5 min, 15 min, 30 min, 1 hr, 4 hr, 8 hr, 24 hr (1 day), 48hr (2 days), 96 hr (4 days), 192 hr (8 days), 14 days, 21 days, and 28days post-dose. It will be appreciated that these time points areexemplary. Different time points and/or more or fewer time points couldbe used in various embodiments. One of ordinary skill in the art wouldselect appropriate time points. The blood samples are typicallyprocessed to obtain plasma or serum prior to making the measurements.Any appropriate method for measuring the compound may be used. Forexample, in some embodiments an immunoassay is used. In someembodiments, a chromatography-based method is used (e.g., liquidchromatography (LC), liquid chromatography-mass spectrometry (LC-MS) orliquid chromatography-tandem mass spectrometry (LC-MS-MS). In someembodiments, a bioassay is used. In many embodiments, the half-life is aterminal (elimination) half-life. In some embodiments, a terminalhalf-life is calculated following administration of a single dose. Insome embodiments, a terminal half-life is calculated followingadministration of multiple doses and allowing the concentration to reachsteady state. In some embodiments, a half-life determined for theinitial (distribution) phase is used. For example, if the majority ofthe compound is removed from circulation during the distribution phase,an initial half-life may be used in some embodiments.

In some embodiments, half-life is determined by conducting a PK analysisusing non-compartmental analysis on multiple dose PK data from a groupof subjects. In some embodiments, half-life is determined by conductinga PK analysis using a standard 1-compartment model on multiple dose PKdata from a group of subjects. In some embodiments, a half-life isdetermined in subjects who are healthy and not known to be sufferingfrom a disorder. In some embodiments, a half-life is determined insubjects suffering from a complement-mediated disorder. In someembodiments, a half-life is determined in adults (persons at least 18years of age). A variety of software tools are available to facilitatecalculation of PK parameters. For example, Phoenix NMLE or PhoenixWinNonlin software (PharSight Corp, St. Louis, Mo.) or Kinetica (ThermoScientific) can be used. It will be appreciated that a reasonableestimate of half-life based on a model can be used.

In some embodiments, a compstatin analog is a multivalent compoundcomprising a plurality of compstatin analog moieties covalently ornoncovalently linked to a polymeric backbone or scaffold. The compstatinanalog moieties can be identical or different. In certain embodiments ofthe invention the multivalent compound comprises multiple instances, orcopies, of a single compstatin analog moiety. In other embodiments ofthe invention the multivalent compound comprises one or more instancesof each of two of more non-identical compstatin analog moieties, e.g.,3, 4, 5, or more different compstatin analog moieties. In certainembodiments of the invention the number of compstatin analog moieties(“n”) is between 2 and 6. In other embodiments of the invention n isbetween 7 and 20. In other embodiments of the invention n is between 20and 100. In other embodiments n is between 100 and 1,000. In otherembodiments of the invention n is between 1,000 and 10,000. In otherembodiments n is between 10,000 and 50,000. In other embodiments n isbetween 50,000 and 100,000. In other embodiments n is between 100,000and 1,000,000. The compstatin analog moieties may be attached directlyto the polymeric scaffold or may be attached via a linking moiety thatconnects the compstatin analog moiety to the polymeric scaffold. Thelinking moiety may be attached to a single compstatin analog moiety andto the polymeric scaffold. Alternately, a linking moiety may havemultiple compstatin analog moieties joined thereto so that the linkingmoiety attaches multiple compstatin analog moieties to the polymericscaffold.

In some embodiments, a compstatin analog comprises an amino acid havinga side chain comprising a primary or secondary amine, e.g., a Lysresidue. For example, any of the compstatin analog sequences disclosedherein may be extended or modified by addition of a linker comprisingone or more amino acids, e.g., one or more amino acids comprising aprimary or secondary amine, e.g., in a side chain thereof. For example,a Lys residue, or a sequence comprising a Lys residue, is added at theN-terminus and/or C-terminus of the compstatin analog. In someembodiments, the Lys residue is separated from the cyclic portion of thecompstatin analog by a rigid or flexible spacer. A linker or spacer may,for example, comprise a substituted or unsubstituted, saturated orunsaturated alkyl chain, oligo(ethylene glycol) chain, and/or othermoieties. The length of the chain may be, e.g., between 2 and 20 carbonatoms. In some embodiments the spacer is or comprises a peptide. Thepeptide spacer may be, e.g., between 1 and 20 amino acids in length,e.g., between 4 and 20 amino acids in length. Suitable spacers cancomprise or consist of multiple Gly residues, Ser residues, or both, forexample. Optionally, the amino acid having a side chain comprising aprimary or secondary amine and/or at least one amino acid in a spacer isa D-amino acid. A PEG moiety or similar molecule or polymeric scaffoldmay be linked to the primary or secondary amine, optionally via alinker. In some embodiments, a bifunctional linker is used. Abifunctional linker may comprise two reactive functional groups, whichmay be the same or different in various embodiments. In variousembodiments, one or more linkers, spacers, and/or techniques ofconjugation described in Hermanson, supra, is used.

Any of a variety of polymeric backbones or scaffolds could be used. Forexample, the polymeric backbone or scaffold may be a polyamide,polysaccharide, polyanhydride, polyacrylamide, polymethacrylate,polypeptide, polyethylene oxide, or dendrimer. Suitable methods andpolymeric backbones are described, e.g., in WO98/46270 (PCT/US98/07171)or WO98/47002 (PCT/US98/06963). In one embodiment, the polymericbackbone or scaffold comprises multiple reactive functional groups, suchas carboxylic acids, anhydride, or succinimide groups. The polymericbackbone or scaffold is reacted with the compstatin analogs. In oneembodiment, the compstatin analog comprises any of a number of differentreactive functional groups, such as carboxylic acids, anhydride, orsuccinimide groups, which are reacted with appropriate groups on thepolymeric backbone. Alternately, monomeric units that could be joined toone another to form a polymeric backbone or scaffold are first reactedwith the compstatin analogs and the resulting monomers are polymerized.In another embodiment, short chains are prepolymerized, functionalized,and then a mixture of short chains of different composition areassembled into longer polymers.

Compstatin Mimetics

The structure of compstatin is known in the art, and NMR structures fora number of compstatin analogs having higher activity than compstatinare also known (Malik, supra). Structural information may be used todesign compstatin mimetics. In some embodiments, a compstatin mimetic isany compound that competes with compstatin or any compstatin analog(e.g., a compstatin analog whose sequence is set forth in Table 1) forbinding to C3 or a fragment thereof (such as a 40 kD fragment of the βchain to which compstatin binds). In some embodiments, the compstatinmimetic has an activity equal to or greater than that of compstatin. Insome embodiments, the compstatin mimetic is more stable, orallyavailable, or has a better bioavailability than compstatin. Thecompstatin mimetic may be a peptide, nucleic acid, or small molecule. Incertain embodiments the compstatin mimetic is a compound that binds tothe binding site of compstatin as determined in a compstatin-C3structure, e.g., a crystal structure or a 3-D structure derived from NMRexperiments. In certain embodiments the compstatin mimetic is a compoundthat could substitute for compstatin in a compstatin-C3 structure andwould form substantially the same intermolecular contacts with C3 ascompstatin. In certain embodiments the compstatin mimetic is a compoundthat binds to the binding site of a peptide having a sequence set forthin Table 1, e.g., SEQ ID NO: 14, 21, 28, 29, 32, 33, 34, or 36 or incertain embodiments SEQ ID NO: 30 or 31, in a peptide-C3 structure. Incertain embodiments the compstatin mimetic is a compound that couldsubstitute for a peptide having a sequence set forth in Table 1, e.g.,SEQ ID NO: 14, 21, 28, 29, 32, 33, 34, or 36 or in certain embodimentsSEQ ID NO: 30 or 31, in a peptide-C3 structure and would formsubstantially the same intermolecular contacts with C3 as the peptide.In certain embodiments the compstatin mimetic has a non-peptide backbonebut has side chains arranged in a sequence designed based on thesequence of compstatin.

One of skill in the art will appreciate that once a particular desiredconformation of a short peptide has been ascertained, methods fordesigning a peptide or peptidomimetic to fit that conformation are wellknown. See, e.g., G. R. Marshall (1993), Tetrahedron, 49: 3547-3558;Hruby and Nikiforovich (1991), in Molecular Conformation and BiologicalInteractions, P. Balaram & S. Ramasehan, eds., Indian Acad. of Sci.,Bangalore, PP. 429-455), Eguchi M, Kahn M., Mini Rev Med Chem.,2(5):447-62, 2002. Of particular relevance to the present invention, thedesign of peptide analogs may be further refined by considering thecontribution of various side chains of amino acid residues, e.g., forthe effect of functional groups or for steric considerations asdescribed in the art for compstatin and analogs thereof, among others.

It will be appreciated by those of skill in the art that a peptide mimicmay serve equally well as a peptide for the purpose of providing thespecific backbone conformation and side chain functionalities requiredfor binding to C3 and inhibiting complement activation. Accordingly, itis contemplated as being within the scope of the present invention toproduce and utilize C3-binding, complement-inhibiting compounds throughthe use of either naturally-occurring amino acids, amino acidderivatives, analogs or non-amino acid molecules capable of being joinedto form the appropriate backbone conformation. A non-peptide analog, oran analog comprising peptide and non-peptide components, is sometimesreferred to herein as a “peptidomimetic” or “isosteric mimetic,” todesignate substitutions or derivations of a peptide that possesses muchthe same backbone conformational features and/or other functionalities,so as to be sufficiently similar to the exemplified peptides to inhibitcomplement activation. More generally, a compstatin mimetic is anycompound that would position pharmacophores similarly to theirpositioning in compstatin, even if the backbone differs.

The use of peptidomimetics for the development of high-affinity peptideanalogs is well known in the art. Assuming rotational constraintssimilar to those of amino acid residues within a peptide, analogscomprising non-amino acid moieties may be analyzed, and theirconformational motifs verified, by means of the Ramachandran plot (Hruby& Nikiforovich 1991), among other known techniques.

One of skill in the art will readily be able to establish suitablescreening assays to identify additional compstatin mimetics and toselect those having desired inhibitory activities. For example,compstatin or an analog thereof could be labeled (e.g., with aradioactive or fluorescent label) and contacted with C3 in the presenceof different concentrations of a test compound. The ability of the testcompound to diminish binding of the compstatin analog to C3 isevaluated. A test compound that significantly diminishes binding of thecompstatin analog to C3 is a candidate compstatin mimetic. For example,a test compound that diminishes steady-state concentration of acompstatin analog-C3 complex, or that diminishes the rate of formationof a compstatin analog-C3 complex by at least 25%, or by at least 50%,is a candidate compstatin mimetic. One of skill in the art willrecognize that a number of variations of this screening assay may beemployed. Compounds to be screened include natural products, librariesof aptamers, phage display libraries, compound libraries synthesizedusing combinatorial chemistry, etc. The invention encompassessynthesizing a combinatorial library of compounds based upon the coresequence described above and screening the library to identifycompstatin mimetics. Any of these methods could also be used to identifynew compstatin analogs having higher inhibitory activity than compstatinanalogs tested thus far.

Pharmaceutical Compositions and Administration

Suitable preparations, e.g., substantially pure preparations of acompstatin analog or other active agent may be combined withpharmaceutically acceptable carriers or vehicles, etc., to produce anappropriate pharmaceutical composition. The term “pharmaceuticallyacceptable carrier or vehicle” refers to a non-toxic carrier or vehiclethat does not destroy the pharmacological activity of the compound withwhich it is formulated. One of skill in the art will understand that acarrier or vehicle is “non-toxic” if it is compatible withadministration to a subject in an amount appropriate to deliver thecompound without causing undue toxicity. Pharmaceutically acceptablecarriers or vehicles that may be used in the compositions of thisinvention include, but are not limited to, water, physiological saline,Ringer's solution, 5% dextrose, and the like. The composition mayinclude other components as appropriate for the formulation desired,e.g., as discussed below. Supplementary active compounds, e.g.,compounds independently useful for treating a subject suffering fromneuropathic pain, including but not limited to the compounds discussedherein, can also be incorporated into the compositions. The inventionprovides such pharmaceutical compositions comprising a compstatin analogand, optionally, a second active agent useful for treating a subjectsuffering from neuropathic pain.

A pharmaceutical composition can be administered to a subject by anysuitable route of administration including, but not limited to,intravenous, intramuscular, subcutaneously, transdermally, byinhalation, by nasal delivery, intrathecally, intracranially,intraarterially, orally, etc. In some embodiments, a compositioncomprising a compstatin analog is administered intravenously. In someembodiments, a composition comprising a compstatin analog isadministered via a catheter or pump directly into the intrathecal space.In some embodiments, a composition comprising a compstatin analog formsa gel upon administration into the intrathecal space. SeePCT/US2008/078593 (WO/2009/046198). It will be understood that“administration” encompasses directly administering a compound orcomposition to a subject, instructing a third party to administer acompound or composition to a subject, prescribing or suggesting acompound or composition to a subject (e.g., for self-administration),self-administration, and, as appropriate, other means of making acompound or composition available to a subject. In some embodiments, asubject has suffered from neuropathic pain for at least 3, 6, 9, or 12months. In some embodiments, a subject has a condition that isfrequently associated with neuropathic pain, but the subject has notdeveloped neuropathic pain. The compstatin analog is administeredprophylactically, to reduce the likelihood that neuropathic pain willdevelop.

Pharmaceutical compositions suitable for injectable use (e.g.,intravenous administration) or by pump or catheter typically includesterile aqueous solutions (where water soluble) or dispersions andsterile powders for the extemporaneous preparation of sterile injectablesolutions or dispersion. Sterile solutions can be prepared byincorporating the compound, e.g., compstatin analog in the requiredamount in an appropriate solvent, optionally with one or a combinationof ingredients such as buffers such as acetates, citrates, lactates orphosphates; agents for the adjustment of tonicity such as sodiumchloride or dextrose; antibacterial agents such as benzyl alcohol ormethyl parabens; antioxidants such as ascorbic acid, glutathione, orsodium bisulfate; chelating agents such as ethylenediaminetetraaceticacid; and other suitable ingredients etc., as desired, followed byfilter-based sterilization. One of skill in the art will be aware ofnumerous physiologically acceptable compounds that may be included in apharmaceutical composition. Other useful compounds include, for example,carbohydrates, such as glucose, sucrose, lactose; dextrans; amino acidssuch as glycine; polyols such as mannitol. These compounds may, forexample, serve as bulking agents and/or stabilizers, e.g., in a powderand/or when part of the manufacture or storage process involveslyophilization. Surfactant(s) such as Tween-80, Pluronic-F108/F68,deoxycholic acid, phosphatidylcholine, etc., may be included in acomposition, e.g., to increase solubility or to provide microemulsion todeliver hydrophobic drugs. pH can be adjusted with acids or bases, suchas hydrochloric acid or sodium hydroxide, if desired. The parenteralpreparation can be enclosed in ampoules, disposable syringes or infusionbags or multiple dose vials made of glass or plastic. Preferablysolutions for injection are sterile and acceptably free of endotoxin.

Generally, dispersions are prepared by incorporating the active compoundinto a sterile vehicle which contains a basic dispersion medium andappropriate other ingredients from those enumerated above. In the caseof sterile powders for the preparation of sterile injectable solutions,methods of preparation can include vacuum drying and freeze-drying whichyields a powder of the active ingredient plus any additional desiredingredient, e.g., from a previously sterile-filtered solution thereof.It will be understood that the pharmaceutically acceptable compounds andpreparation methods mentioned herein are exemplary and non-limiting.See, e.g., Remington: The Science and Practice of Pharmacy. 21stEdition. Philadelphia, Pa. Lippincott Williams & Wilkins, 2005, foradditional discussion of pharmaceutically acceptable compounds andmethods of preparing pharmaceutical compositions of various types.

In some embodiments, a compstatin analog or other active agent isprepared as a controlled release formulation, e.g., an implant ormicroencapsulated delivery system. In some embodiments, a controlledrelease formulation comprises microparticles or nanoparticles comprisinga compstatin analog. Biodegradable, biocompatible polymers can be used,such as ethylene vinyl acetate, polyanhydrides, polyglycolic acid, PLGA,collagen, polyorthoesters, polyethers, and polylactic acid. Methods forpreparation of such formulations will be apparent to those skilled inthe art. In some embodiments, a controlled release formulation comprisesa gel-forming material. Liposomal suspensions can also be used aspharmaceutically acceptable carriers. These can be prepared according tomethods known to those skilled in the art, for example, as described inU.S. Pat. No. 4,522,811 and other references listed herein. Liposomes,including targeted liposomes (e.g., antibody targeted liposomes) andpegylated liposomes have been described (Hansen C B, et al., BiochimBiophys Acta. 1239(2):133-44, 1995; Torchilin V P, et al., BiochimBiophys Acta, 1511(2):397-411, 2001; Ishida T, et al., FEBS Lett.460(1):129-33, 1999). One of ordinary skill in the art will appreciatethat the materials and methods selected for preparation of a controlledrelease formulation, implant, etc., should be such as to retain activityof the compound.

It will be appreciated that the compstatin analog and/or additionalactive agent(s) can be provided as a pharmaceutically acceptable salt.Pharmaceutically acceptable salts include those derived frompharmaceutically acceptable inorganic and organic acids and bases.Examples of suitable acid salts include acetate, adipate, alginate,aspartate, benzoate, benzenesulfonate, bisulfate, butyrate, citrate,camphorate, camphorsulfonate, cyclopentanepropionate, digluconate,dodecylsulfate, ethanesulfonate, formate, fumarate, glucoheptanoate,glycerophosphate, glycolate, hemisulfate, heptanoate, hexanoate,hydrochloride, hydrobromide, hydroiodide, 2-hydroxyethanesulfonate,lactate, maleate, malonate, methanesulfonate, 2-naphthalenesulfonate,nicotinate, nitrate, oxalate, palmoate, pectinate, persulfate,3-phenylpropionate, phosphate, picrate, pivalate, propionate,salicylate, succinate, sulfate, tartrate, thiocyanate, tosylate andundecanoate. Also, pharmaceutically-acceptable salts can be prepared asalkaline metal or alkaline earth salts, such as sodium, potassium orcalcium salts, if appropriate depending on the identity of the activeagent.

A pharmaceutical composition can be administered in an amount effectiveto achieve a desired therapeutic effect. A variety of clinicalassessment instruments known in the art can be used to assess theseverity of neuropathic pain. “Severity” of neuropathic pain can relateto pain intensity, pain unpleasantness, and/or impact of pain onfunctioning or quality of life, sleep, mood. For example, pain intensitycan be rated on a 0-10 rating scale (0=no pain, 10=worst painimaginable) or using the McGill Pain Questionnaire (0 to 45 scale) orthe short form thereof. A visual analog scale (VAS), numerical ratingscale (NRS), or verbal rating scale (VRS) may be used used. Otherassessment tools include, e.g., the Symptom Score Scale (Kvinesdal etal., Imipramine treatment of painful diabetic neuropathy. JAMA251:1727-1730, 1984), the Neuropathic Pain Scale (Galer B S, Jensen M P(1997). Development and preliminary validation of a pain measurespecific to neuropathic pain: the Neuropathic Pain Scale. Neurology48:332-338, 1997), the Guy/Farrar Patient Global Impression of Change(PGIC) scale, the Multidimensional Pain Inventory (MPI) (Kerns R D, etal., The West Haven-Yale Multidimensional Pain Inventory (WHYMPI). Pain.23:345-356, 1985), or the Pain Relief Scale (Devers A, Galer B S,Topical lidocaine patch relieves a variety of neuropathic painconditions: an open-label study. Clin J Pain 16:205-208, 2000). Theintensity of the different pain components that a subject may report(spontaneous ongoing pain, spontaneous paroxysmal pain, dysesthesiae andparesthesiae) or the evoked pains (allodynia and hyperalgesia), and/orpain worsening with movement, can be assessed. For example, reduction incharacteristics of neuropathic pain such as those assessed in the LANSSscale can be assessed. The impact of pain on functioning or quality oflife can be assessed using, e.g., an SF-36 score, Bodily Pain IndexInterference score, Oswestry Disability Index score, and/or Euro QoLscore. Further non-limiting discussion of outcome measures that could beused is found in, e.g., Dworkin R H, Pain. 113(1-2):9-19, 2005; Bryce, TN, et al., J Spinal Cord Med. 30(5): 421-440, 2007, guidelines forassessment of neuropathic pain established by the European Federation ofNeurological Societies (EFNS) and references in any of the foregoing. Insome embodiments, an effective amount produces a statisticallysignificant improvement in pain intensity, physical functioning, qualityof life, and/or emotional functioning.

In some embodiments, an effective amount produces significant painrelief, e.g., at least a 20% reduction in pain score. In someembodiments, an effective amount produces at least a 30% reduction inpain score. In some embodiments, an effective amount produces at least a40% reduction in pain score. In some embodiments, an effective amountproduces at least a 50% reduction in pain score. In some embodiments, aneffective amount produces a reduction of at least 2, 3, 4, or 5 pointsin a 10 or 11 point pain intensity scale. In some embodiments, suchreduction (e.g., at least 20%, 30%, 40%, 50%, or more, and/or areduction of at least 2, 3, 4, or 5 points on 10 or 11 point scale) ispresent in at least 5%, 10%, 20%, or more of a group of subjectstreated. In some embodiments, an effective amount results in a betteraverage functional status after 1, 3, or 6 months, in a group ofsubjects who received a compstatin analog as compared with a group ofcontrol subjects.

In some embodiments, treatment with a compstatin analog results inreduced incidence and/or severity of side effects relative to treatmentwith conventional therapy for neuropathic pain. For example, there maybe reduced dizziness, vertigo, somnolence, sedation, fatigue, lethargy,dry mouth, ataxia, gait disturbance, constipation, and/or posturalhypotension. In some embodiments, a conventional therapy is a therapydiscussed in, Attal, N., et al., EFNS guidelines on pharmacologicaltreatment of neuropathic pain. European Journal of Neurology 2006, 13:1153-1169, 2006 and/or in Chou R, et al., Drug C1ass Review on Drugs forNeuropathic Pain. 2007 (available athttp://www.ohsu.edu/drugeffectiveness/reports/final.cfm). In someembodiments such conventional therapy is approved by a government agencyresponsible for regulating pharmaceutical agents, such as the U.S. Food& Drug Administration or the European Medicines Evaluation Agency, foruse in treating neuropathic pain.

In accordance with certain embodiments of the invention a pharmaceuticalcomposition comprising a compstatin analog is administered parenterallyfor treatment of neuropathic pain. In some embodiments, the compositionis administered intravenously. In some embodiments, the composition isadministered by intravenous injection. In some embodiments thecomposition is administered as an IV bolus or an IV infusion. In someembodiments the composition is administered as an IV drip. In someembodiments the composition is administered as an IV bolus followed byan IV infusion or IV drip. In some embodiments an IV infusion isadministered over about 1, 2, 3, 4, 5, 15, 20, 30, or 60 minutes. Insome embodiments an IV drip is administered over more than 60 minutes,e.g., over about 1, 2, 3, or more hours. In some embodiments, a totalamount of between about 0.1 mg/kg and about 2,000 mg/kg of compstatinanalog is administered, e.g., between about 1 mg/kg and about 1,000mg/kg, e.g., between about 5 mg/kg and about 500 mg/kg, e.g., within a24 hour period. In some embodiments, a total amount of between about 10mg/kg and about 100 mg/kg of compstatin analog is administered, e.g.,between about 10 mg/kg and about 50 mg/kg, e.g., between about 10 mg/kgand about 20 mg/kg, e.g., within a 24 hour period.

In some embodiments, the invention provides a compstatin analog orpharmaceutical composition comprising a compstatin analog, packagedtogether with a package insert (label) approved by a government agencyresponsible for regulating pharmaceutical agents, e.g., the U.S. Food &Drug Administration, specifying neuropathic pain and/or one or moreindication(s) associated with neuropathic pain as indication(s) forwhich the composition and/or compstatin analog has been approved foruse. In some embodiments, a package insert states particular patientand/or disease characteristics or criteria that define a patientpopulation or disease category for treatment of which the compositionhas been approved for use. In some embodiments, a package insertdescribes an appropriate dose, dose range, and/or administration routeor method for treating a subject suffering from neuropathic pain. Insome embodiments, the invention provides a pharmaceutical packcomprising: (a) a compstatin analog in concentrated or solid form (e.g.,as a lyophilized powder); (b) a pharmaceutically acceptable carrier,diluent, or vehicle. In some embodiments, a suitable carrier, diluent,or vehicle may be provided separately or acquired by a health careprovider from an appropriate source. Optionally a pack or label contains(e.g., in addition to specifying neuropathic pain and/or one or moreindication(s) associated with neuropathic pain as indication(s) forwhich the composition and/or compstatin analog has been approved foruse) instructions for dissolving or diluting the compstatin analog in acarrier, diluent, or vehicle to produce a composition foradministration.

In some embodiments, a compstatin analog is administered daily. It willbe appreciated that a variety of different dosing regimens could be usedto administer a desired total daily amount. For example, a desiredamount of compstatin analog could be administered in a singleadministration or in multiple administrations, e.g., during a 24 hourperiod. For example, a subject could receive two doses within a 24 hourperiod, which doses could be administered over the same length of timeor over different lengths of time. In some embodiments, a compstatinanalog is administered at time intervals greater than 24 hours. Forexample, doses could be administered on average every other day, every3-4 days, weekly, every 10 days, every 2 weeks, monthly, etc. Treatmentcan continue for, e.g., months, years, or indefinitely.

The invention encompasses administration of a compstatin analog incombination with additional therapy. Such additional therapy mayinclude, but is not limited to, administration of any agent(s) used inthe art or potentially useful for treating a subject suffering fromneuropathic pain and/or suffering from a condition associated withneuropathic pain. Examples include, e.g., antidepressants (e.g., SSRIs,TCAs), anticonvulsants, NMDA antagonists, topical anesthetics or othertopical agents (e.g., lidocaine, capsaicin), opioid analgesics, sodiumchannel blockers, etc. See, e.g., Chou R, et al., Drug C1ass Review onDrugs for Neuropathic Pain. 2007 (available athttp://www.ohsu.edu/drugeffectiveness/reports/final.cfm), Gilron, I., etal., CMAJ, 175(3): 265-275, 2006; and/or Attal N, et al., Eur J Neurol.2010 Apr. 9. [Epub ahead of print].

When two or more therapies (e.g., compounds or compositions) are used oradministered “in combination” with each other, they may, for example, begiven at the same time, within overlapping time periods, or sequentially(e.g., separated by up to about 2, 4, or 6 weeks in time, or more), invarious embodiments of the invention. They may be administered via thesame route or different routes. In some embodiments, the compounds orcompositions are administered within 48 hours of each other. In someembodiments, a compstatin analog can be given prior to or afteradministration of the additional compound(s), e.g., sufficiently closein time that the compstatin analog and additional compound(s) arepresent at useful levels within the body at least once. In someembodiments, the compounds or compositions are administered sufficientlyclose together in time such that no more than 90% of the earlieradministered composition has been metabolized to inactive metabolites oreliminated, e.g., excreted, from the body, at the time the secondcompound or composition is administered.

In some embodiments, a composition that includes both the compstatinanalog and additional compound(s) is administered. In some aspects, theinvention provides a composition comprising a compstatin analog and asecond agent useful for treating neuropathic pain and/or for treating acondition associated with neuropathic pain.

One of skill in the art can select an appropriate amount and/or dose ofother agent(s) described herein that may be used in conjunction with acompstatin analog. For example, e.g., in some embodiments an amount ordose ranging from about 0.001 mg/kg to 1,000 mg/kg body weight, e.g.,about 0.01 to 25 mg/kg body weight, e.g., about 0.1 to 20 mg/kg bodyweight, e.g., about 1 to 10 mg/kg of a compound described herein isadministered at various intervals and over different periods of time asappropriate. The skilled artisan will appreciate that certain factorscan influence the total amount, dosage(s) and timing required toeffectively treat a subject, including but not limited to the severityof the pain, other treatments being administered, the general healthand/or age of the subject, and diseases that may be present.

Those skilled in the art will recognize, or be able to ascertain usingno more than routine experimentation, many equivalents to the specificembodiments of the invention described herein. The scope of the presentinvention is not intended to be limited to the above Description, butrather is as set forth in the appended claims. It will be appreciatedthat the invention is in no way dependent upon particular resultsachieved in any specific example or with any specific embodiment. In theclaims articles such as “a”, “an” and “the” may mean one or more thanone unless indicated to the contrary or otherwise evident from thecontext. Claims or descriptions that include “or” between one or moremembers of a group are considered satisfied if one, more than one, orall of the group members are present in, employed in, or otherwiserelevant to a given product or process unless indicated to the contraryor otherwise evident from the context. The invention includesembodiments in which exactly one member of the group is present in,employed in, or otherwise relevant to a given product or process. Forexample, and without limitation, it is understood that where claims ordescription indicate that a residue at a particular position may beselected from a particular group of amino acids or amino acid analogs,the invention includes individual embodiments in which the residue atthat position is any of the listed amino acids or amino acid analogs.The invention also includes embodiments in which more than one, or allof the group members are present in, employed in, or otherwise relevantto a given product or process. Furthermore, it is to be understood thatthe invention encompasses all variations, combinations, and permutationsin which one or more limitations, elements, clauses, descriptive terms,etc., from one or more of the listed claims and/or relevant descriptionherein is introduced into another claim. For example, any claim that isdependent on another claim can be modified to include one or moreelements, limitations, clauses, or descriptive terms, found in any otherclaim that is dependent on the same base claim. Furthermore, where theclaims recite a composition, it is to be understood that methods ofadministering the composition according to any of the methods disclosedherein, and methods of using the composition for any of the purposesdisclosed herein are included within the scope of the invention, andmethods of making the composition according to any of the methods ofmaking disclosed herein are included within the scope of the invention,unless otherwise indicated or unless it would be evident to one ofordinary skill in the art that a contradiction or inconsistency wouldarise. Methods of treating a subject can include a step of providing asubject in need of such treatment (e.g., a subject who has neuropathicpain or a condition associated with neuropathic pain, has hadneuropathic pain or a condition associated with neuropathic pain, or isat increased risk of having or developing neuropathic pain or acondition associated with neuropathic pain), a step of diagnosing asubject as having neuropathic pain or as having a condition associatedwith neuropathic pain or increased risk of neuropathic pain, and/or astep of selecting a subject for treatment with a compstatin analog,e.g., as a result of the subject suffering from neuropathic pain or acondition associated with neuropathic pain. In some embodiments,increased risk is at least 1.5-fold, e.g., at least 2-fold the risk ofan average subject, e.g., a subject reasonably matched at least withregard to one or more characteristics such as age, gender, etc.

Where elements are presented as lists, e.g., in Markush group format, itis to be understood that each subgroup of the elements is alsodisclosed, and any element(s) can be removed from the group. Forpurposes of conciseness only some of these embodiments have beenspecifically recited herein, but the invention includes all suchembodiments. It should also be understood that, in general, where theinvention, or aspects of the invention, is/are referred to as comprisingparticular elements, features, etc., certain embodiments of theinvention or aspects of the invention consist, or consist essentiallyof, such elements, features, etc.

Where ranges are given, endpoints are included. Furthermore, it is to beunderstood that unless otherwise indicated or otherwise evident from thecontext and understanding of one of ordinary skill in the art, valuesthat are expressed as ranges can assume any specific value or subrangewithin the stated ranges in different embodiments of the invention, tothe tenth of the unit of the lower limit of the range, unless thecontext clearly dictates otherwise. In addition, it is to be understoodthat any particular embodiment, aspect, element, feature, etc., of thepresent invention may be explicitly excluded from any one or more of theclaims even if such exclusion is not set forth explicitly herein.

We claim:
 1. A method of treating a subject in need of treatment forneuropathic pain, the method comprising administering a compstatinanalog to the subject.
 2. The method of claim 1, wherein the compstatinanalog is administered intravenously.
 3. The method of claim 1, whereinthe activity of the compstatin analog is at least 100 times as great asthe activity of compstatin as measured in an in vitro assay.
 4. Themethod of claim 1, wherein the compstatin analog is a compound thatcomprises a cyclic peptide having a core sequence ofX′aa-Gln-Asp-Xaa-Gly (SEQ ID NO: 3), where X′aa and Xaa are selectedfrom Trp and analogs of Trp.
 5. The method of claim 1, wherein thecompstatin analog is a compound that comprises a cyclic peptide having acore sequence of X′aa-Gln-Asp-Xaa-Gly-X″aa (SEQ ID NO: 4), where X′aaand Xaa are each independently selected from Trp and analogs of Trp andX″aa is selected from His, Ala, single methyl unbranched amino acids,Phe, Trp, and analogs of Trp.
 6. The method of claim 5, wherein thepeptide has a sequence ofX′aa1-X′aa2-X′aa3-X′aa-Gln-Asp-Xaa-Gly-X″aa-X″aa2-X″aa3-X″aa4-X″aa5 (SEQID NO: 5), and X′aa1, X′aa2, X′aa3, X″aa2, X″aa3-X″aa4, and X″aa5 areidentical to the amino acids at the corresponding positions incompstatin.
 7. The method of claim 1, wherein the compstatin analog is acompound that comprises a cyclic peptide having a sequence ofX′aa1-X′aa2-X′aa3-X′aa4-Gln-Asp-Xaa-Gly-X″aa1-X″aa2-X″aa3-X″aa4-X″aa5(SEQ ID NO: 5), where X′aa4 and Xaa are selected from Trp and analogs ofTrp, wherein X′aa1, X′aa2, X′aa3, X″aa1, X″aa2, X″aa3, X″aa4, and X″aa5are independently selected from among amino acids and amino acidanalogs, and the peptide is cyclized via a bond between X′aa2 and X″aa4.8. The method of claim 7, wherein X′aa1, X′aa2, X′aa3, X″aa2, X″aa3,X″aa4, and X″aa5 are identical to the amino acids at the correspondingpositions in compstatin and X″aa1 is Ala or a single methyl unbranchedamino acid.
 9. The method of claim 1, wherein the compstatin analog is acompound that comprises a cyclic peptide having a sequence:(SEQ ID NO: 6) Xaa1-Cys-Val-Xaa2-Gln-Asp-Xaa2*-Gly*-Xaa3-His-Arg-Cys-Xaa4;

wherein: Xaa1 is Ile, Val, Leu, B¹-Ile, B¹-Val, B¹-Leu or a dipeptidecomprising Gly-Ile or B¹-Gly-Ile, and B¹ represents a first blockingmoiety; Xaa2 and Xaa2* are independently selected from Trp and analogsof Trp; Xaa3 is His, Ala or an analog of Ala, Phe, Trp, or an analog ofTrp; Xaa4 is L-Thr, D-Thr, Ile, Val, Gly, a dipeptide selected fromThr-Ala and Thr-Asn, or a tripeptide comprising Thr-Ala-Asn, wherein acarboxy terminal —OH of any of the L-Thr, D-Thr, Ile, Val, Gly, Ala, orAsn optionally is replaced by a second blocking moiety B²; and the twoCys residues are joined by a disulfide bond.
 10. The method of claim 9,wherein Xaa1 is Ile, Val, Leu, Ac-Ile, Ac-Val, Ac-Leu or a dipeptidecomprising Gly-Ile or Ac-Gly-Ile; Xaa2 and Xaa2* are independentlyselected from Trp and analogs of Trp; Xaa3 is His, Ala or an analog ofAla, Phe, Trp, or an analog of Trp; Xaa4 is L-Thr, D-Thr, Ile, Val, Gly,a dipeptide selected from Thr-Ala and Thr-Asn, or a tripeptidecomprising Thr-Ala-Asn, wherein a carboxy terminal —OH of any of theL-Thr, D-Thr, Ile, Val, Gly, Ala, or Asn optionally is replaced by —NH₂.11. The method of claim 9, wherein Xaa2 is an analog of Trp havingincreased hydrophobic character relative to Trp.
 12. The method of claim9, wherein Xaa2 is an analog of Trp comprising a substituted orunsubstituted bicyclic aromatic ring component or two or moresubstituted or unsubstituted monocyclic aromatic ring components. 13.The method of claim 9, wherein Xaa2* is an analog of Trp having anelectronegative substituent on the indole ring and not having increasedhydrophobic character relative to Trp.
 14. The method of claim 9,wherein the compstatin analog has a sequence selected from the groupconsisting of: SEQ ID NOs: 9-36
 15. The method of claim 9, wherein thecompstatin analog has a sequence selected from the group consisting of:SEQ ID NOs: 14, 21, 28, 29, 32, 33, 34, or
 36. 16. The method of claim9, wherein the compstatin analog has the sequence of SEQ ID NO: 28, 32,or
 34. 17. The method of claim 1, wherein the compstatin analog is acompound that comprises a cyclic peptide having a sequence ofX′aa1-X′aa2-X′aa3-X′aa4-Gln-Asp-Xaa-Gly-X″aa1-X″aa2-X″aa3-X″aa4-X″aa5(SEQ ID NO: 5), where X′aa4 and Xaa are selected from Trp and analogs ofTrp, wherein X′aa1, X′aa2, X′aa3, X″aa1, X″aa2, X″aa3, X″aa4, and X″aa5are independently selected from among amino acids and amino acidanalogs, X′aa2 and X″aa4 are not Cys, and the peptide is cyclized via abond between X′aa2 and X″aa4.
 18. The method of claim 17, wherein X′aa1,X′aa3, X″aa2, X″aa3, and X″aa5 are identical to the amino acids at thecorresponding positions in compstatin and X″aa1 is Ala or a singlemethyl unbranched amino acid.
 19. The method of claim 17, wherein thebond is an amide bond, wherein one of X′aa2 and X″aa4 is an amino acidor amino acid analog having a side chain that comprises a primary orsecondary amine, the other one of X′aa2 and X″aa4 is an amino acid oramino acid analog having a side chain that comprises a carboxylic acidgroup, and the bond is an amide bond.
 20. The method of claim 1, whereinthe peptide is acetylated at the N-terminus, amidated at the C-terminus,or both acetylated at the N-terminus and amidated at the C-terminus. 21.The method of claim 1, further comprising: administering a conventionaltreatment for neuropathic pain to the subject.